Environmental Factors Affecting Thyroid-Stimulating Hormone and Thyroid Hormone Levels

Spatial distribution and risk assessment of perchlorate in raw cow milk from China

Perchlorate is a ubiquitous environmental contaminant worldwide, recognized as an emerging thyroid toxicant. This study focused on the pollution status, spatial distribution, possible sources of perchlorate in raw cow milk collected from 155 dairy farms in China, as well as the health risk of exposure to perchlorate through dairy products. The results showed that the detection rate of perchlorate in raw milk was 100% with the mean of 15.9 μg/kg, indicating the ubiquitous contamination of perchlorate in raw milk from China. The simulation of spatial distributions indicated that the levels of perchlorate in raw milk were spatially correlated, and relatively high levels of perchlorate exist in certain parts of Beijing-Tianjin-Hebei, Shanxi, Henan, and Zhejiang, suggesting potential environmental perchlorate contamination in these regions. A positive correlation was found between the perchlorate level in milk and the perchlorate level in feed, indicating the transfer process of perchlorate from feed to milk. The hazard quotient (HQ) values of exposure to perchlorate by dairy products ranged between 0 and 2.14, with the mean of 0.0188 and P95 of 0.101, indicating relatively low health risk to perchlorate through dairy products. To our knowledge, this is the first nationwide study on the spatial distribution and risk assessment of perchlorate in raw cow milk from China.

Thyroid-stimulating hormone (TSH) mediates the associations between maternal metals and neurodevelopment in children: A prospective cohort study

Insufficient research has focused on the effects of metal mixtures on children's neurodevelopment and TSH's potential mediating effect. Plasma concentrations of ten metals were measured among 2887 pregnant women in a persistent Chinese birth cohort. At age two, children's neurodevelopment was assessed using mental development indexes (MDIs) and psychomotor development indexes (PDIs), defining neurodevelopmental delay as MDI≤ 79 (cognitive delay) or PDI≤ 79 (motor delay). The associations between single and mixed metals with neurodevelopment delay risk were examined using generalized linear regression complemented by weighted quantile sum (WQS) regression. To investigate the mediated effects of infant Thyroid-Stimulating Hormone (TSH) on metal-associated neurodevelopment delay risk, mediation analyses were conducted. According to the single-metal model, V, Mn, and Pb levels are positively associated with neurodevelopment delay. The WQS model found consistent associations (Odds Ratio [OR] 1.55, 95% Confidence Interval [CI] 1.23 to 1.95), highlighting V, Mn, and Pb as the main causes of cognitive delay. Further mediation analysis revealed that the association between metals (mainly V, Mn, and Pb) and neurodevelopment delay risk is mediated by TSH, with proportions ranging from 3.18 to 10.14% (all P < 0.05). Our findings highlighted prenatal exposure to metals was associated with higher risks of neurodevelopmental delay, with TSH possibly mediating this effect.

Frequency and Determinants of Levothyroxine Therapy Initiation for Veterans with Subclinical Hypothyroidism

Background/Objectives: There is evidence of overtreatment in patients with subclinical hypothyroidism (SCH). We aimed to identify the proportion of patients treated for SCH and the determinants of thyroid hormone therapy initiation. Methods: We included a random sample of adult Veterans diagnosed with SCH from 1 January 2016 to 31 December 2018 and conducted univariate and multivariable logistic regression to identify factors associated with levothyroxine initiation. Results: Out of 229 Veterans with SCH [90.0% male, 87.2% White, 99.1% non-Hispanic, median age (interquartile range; IQR) 68 (17) years], 27.5% were treated with levothyroxine. The treated group had a higher proportion of White patients (95.2% vs. 84.2%, p = 0.039), a higher thyrotropin level [median (IQR), 6.98 (2.06) mIU/L vs. 6.14 (1.10) mIU/L, p = 0.0002], a higher proportion of patients with thyrotropin level ≥ 10 mIU/L (11.1% vs. 3.0%, p = 0.021), a lower frequency of confirmatory thyroid testing before initiating levothyroxine (49.2% vs. 97.0%, p < 0.0001), and a similar frequency of thyroid autoimmunity testing (3.2% vs. 0.6%, p = 0.18) compared to the untreated group. In a multivariable logistic regression analysis, White race (OR = 4.50, 95% CI 1.19 to 17.08, p = 0.026) and index thyrotropin level [OR = 1.71, 95% CI 1.24 to 2.35, p = 0.001; for every SD increase (1.6 mIU/L)] were associated with higher odds of treatment. Conclusions: Three in 10 Veterans with SCH received levothyroxine, often based on a single abnormal thyroid test without autoimmunity assessment. White race and higher thyrotropin level were linked to increased odds of starting treatment, indicating potential disparities and the influence of SCH severity on decision-making.

Zinc and Ferritin Levels and Their Associations with Functional Disorders and/or Thyroid Autoimmunity: A Population-Based Case-Control Study

Population zinc and iron status appear to be associated with an increased risk of thyroid function abnormalities and thyroid autoimmunity (AITD). In the present study, we aimed to determine whether zinc and/or iron levels (assessed by ferritin levels) were associated with the presence of AITD and with alterations in thyroid function. A population-based case-control study (n = 1048) was conducted (cases: n = 524; controls: n = 524). Participants were measured for blood concentrations of zinc and ferritin, TSH, FT4, FT3, and thyroid autoantibodies. No significant differences were found in relation to ferritin levels between cases and controls. Among cases, the prevalence of low zinc levels in those with hypothyroidism (both subclinical and overt) was 49.1% [odds ratio (OR) of low zinc levels: 5.926; 95% CI: 3.756-9.351]. The prevalence of low zinc levels in participants with hyperthyroidism (both subclinical and overt) was 37.5% [OR of low zinc levels: 3.683; 95% CI: 1.628-8.33]. The zinc value that best discriminated the highest frequency of AITD was 70.4 µg/dL [sensitivity: 0.947, 1-specificity: 0.655, specificity: 0.345]. The highest frequency of AITD was calculated based on a zinc value <70 µg/dL (relative to a normal value), with this frequency being significantly higher in cases than in controls [OR: 9.3; 95% CI: 6.1-14.3 (p = 0.001)]. In conclusion, the results of our study suggest that zinc deficiency is associated with an increased frequency of functional thyroid disorders and thyroid autoimmunity.

IL-17 and IL-38 gene polymorphisms in thyroid-associated ophthalmopathy

BACKGROUND

Thyroid-associated ophthalmopathy (TAO) is an autoimmune condition commonly linked with Graves' disease (GD), characterized by orbital tissue inflammation and fibrosis. It is hypothesized that gene polymorphisms may influence production of the IL-17 and IL-38 cytokines, thereby impacting TAO development and progression. This study focused on investigating the gene polymorphisms of IL-17 (rs9463772 C/T in IL17F) and IL-38 (rs3811058 C/T, rs7570267 A/G in IL1F10) in patients with GD.

METHODS

A case-control study was conducted on 132 patients with TAO and 153 patients without TAO according to eligibility criteria. After clinical examination blood samples were collected for further investigations. Genotyping was performed with the TaqMan™ Master Mix kit. Allele and genotype frequencies were compared between studied groups and subgroups.

RESULTS

No significant differences were found in age, duration of GD, or thyroid hormone between patients with and without TAO. However, a higher predisposition to develop TAO was observed among smokers (OR = 1.682, p = 0.03). Overall, no significant associations between gene polymorphisms and TAO development were identified in GD patients. Further analysis revealed that the CC genotype in IL1F10 rs3811058 polymorphism among Caucasians was associated with an increased risk of TAO (OR = 2.7, p = 0.02), as well as allele differences were also significant (OR = 2.8, p = 0.001).

CONCLUSIONS

These findings shed light on TAO genetic predispositions in Kazakhstani GD patients, notably among Caucasians, underscoring the need for further research. These results may offer valuable targets for the development of novel treatments for TAO.

The possible protective effect of ginger extract on toxic changes induced by bisphenol A on the thyroid gland of adult male albino rats: light and electron microscopic study

Bisphenol A (BPA) is a chemical substance used in the plastic industry and considered as an endocrine disruptor. Ginger is a herbal material used in the food industry and has antioxidant activity. The present study was performed to evaluate the histological changes in the thyroid gland of adult male albino rats after intake of BPA and if there is any protective role for ginger extract (GE). Eighty adult male rats were divided equally into four groups. Group I as a control group, group II included rats that received 250 mg/kg/day GE orally for eight weeks, group III included rats that received 200 mg/kg/day BPA orally for the same period and group IV included rats that received BPA in the same dose for the same duration concomitantly with GE. At the end of the experiment, blood samples were taken for hormonal essay and tissue samples were processed. Light and electron microscopic studies were done. Morphometric and statistical studies were carried out. Group III showed degenerative changes in the thyroid gland, decreased serum levels of T3 and T4 and a strong positive inducible nitric oxide synthase (iNOS) immune response. Group IV showed restoration of thyroid gland architecture and function. In conclusion, GE protected the thyroid structure from the damaging effect of BPA oxidative stress through its anti-oxidant effect, thus preserving thyroid activity.

Bidirectional negative relationship between thyrotropin and kidney function during alcohol intoxication in males

Introduction

Despite a well-established direct toxic effect of alcohol on renal cells, there is a salutary dose-dependent effect of alcohol consumption on common laboratory parameters related to kidney performance. Alcohol also impacts thyroid hormones, while thyroid status modulates kidney function. The modulation of kidney parameters with thyrotropin (TSH) and thyroid status indicates a possible interaction between alcohol, kidney, and thyroid functions. This retrospective study was conducted to test the hypothesis that the positive effect of alcohol use on the estimated glomerular filtration rate (eGFR) is mediated by alcohol's effect on thyroid hormones.

Methods

We reviewed the electronic medical records of 767 hospitalized adult patients free of thyroid disorders who received medical care in the Mayo Clinic Health System from June 2019 through June 2022 and had blood alcohol concentration (BAC), serum TSH, and serum creatinine measured during the hospitalization. We calculated the eGFR using both the re-expressed Modification of Diet in Renal Disease (MDRD II) study equation and the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) Creatinine equation.

Results

We found a significant relationship of BAC with eGFR (CKD-EPI) and TSH in males only. BAC had a positive association with eGFR (b = 0.24, p = 0.0001) and negative with TSH (b=-0.17, p = 0.006). The covariance between the two outcomes (eGFR and TSH) was negative (b = -0.12, p = 0.049). The path analyses using the eGFR MDRD II equation were not significant in males, whereas females had no significant path analyses with either of the eGFR equations.

Discussion

We observed that BAC influences both eGFR and TSH, whereas eGFR and TSH influence each other. After considering important covariates (e.g., age, body mass index, diabetes mellitus, cardiovascular disease, chronic kidney disease, and chronic liver disease) and the negative bidirectional effect of TSH and eGFR, a positive impact of BAC on eGFR was observed in males.

Association Between Particulate Matter Exposure and Preterm Birth in Women With Abnormal Preconception Thyrotropin Levels: Large Cohort Study

Background

Prior research has linked exposure to particulate matter with an aerodynamic diameter of ≤2.5 μm (PM2.5) with preterm birth (PTB). However, the modulating effect of preconception thyroid stimulating hormone (TSH) levels on the relationship between PM2.5 exposure and PTB has not been investigated.

Objective

This study aimed to assess whether preconception TSH levels modulate the impact of PM2.5 exposure on PTB.

Methods

This cohort study was conducted in Guangdong, China, as a part of the National Free Pre-Pregnancy Checkups Project. PM2.5 exposure was estimated by using the inverse distance weighting method. To investigate the moderating effects of TSH levels on trimester-specific PM2.5 exposure and PTB, we used the Cox proportional hazards model. Additionally, to identify the susceptible exposure windows for weekly specific PM2.5 exposure and PTB, we built distributed lag models incorporating Cox proportional hazards models.

Results

A total of 633,516 women who delivered between January 1, 2014, to December 31, 2019, were included. In total, 34,081 (5.4%) of them had abnormal preconception TSH levels. During the entire pregnancy, each 10-μg/m3 increase in PM2.5 was linked to elevated risks of PTB (hazard ratio [HR] 1.559, 95% CI 1.390-1.748), early PTB (HR 1.559, 95% CI 1.227-1.980), and late PTB (HR 1.571, 95% CI 1.379-1.791) among women with abnormal TSH levels. For women with normal preconception TSH levels, PM2.5 exposure during the entire pregnancy was positively associated with the risk of PTB (HR 1.345, 95% CI 1.307-1.385), early PTB (HR 1.203, 95% CI 1.126-1.285), and late PTB (HR 1.386, 95% CI 1.342-1432). The critical susceptible exposure windows were the 3rd-13th and 28th-35th gestational weeks for women with abnormal preconception TSH levels, compared to the 1st-13th and 21st-35th gestational weeks for those with normal preconception TSH levels.

Conclusions

PM2.5 exposure was linked with a higher PTB risk, particularly in women with abnormal preconception TSH levels. PM2.5 exposure appears to have a greater effect on pregnant women who are in the early or late stages of pregnancy.

Morphological and physiological features in small ruminants: an adaptation strategy for survival under changing climatic conditions

Climate change due to natural human activity is a significant global phenomenon affecting the sustainability of most countries' livestock industries. Climate change factors such as ambient temperature, relative humidity, direct and indirect sun radiation, and wind have significant consequences on feed, water, pasture availability, and the re-emergence of diseases in livestock. All these variables have a considerable impact on livestock production and welfare. However, animals' ability to respond and adapt to changes in climate differs within species and breeds. Comparatively, small ruminants are more adaptive to the adverse effects of climate change than large ruminants in terms of reproduction performance, survival, production yield, and resistance to re-emerging diseases. This is mainly due to their morphological features against harsh climate effects. Tropical breeds are more adaptive to the adverse effects of climate change than small temperate ruminants. However, the difference in morphological characteristics towards adaptation to the impact of climate change will guide the development of suitable policies on the selection of breeding stock suitable for different regions in the world. The choice of breeds based on morphological features and traits is an essential strategy in mitigating and minimizing the effects of climate change on small ruminants' production and welfare. This review highlights the adaptive morphological features within and among breeds of small ruminants toward adaptation to climate change.

SGLT2 inhibitor as a potential therapeutic approach in hyperthyroidism-induced cardiopulmonary injury in rats

Hyperthyroidism-induced cardiac disease is an evolving health, economic, and social problem affecting well-being. Sodium-glucose cotransporter protein 2 inhibitors (SGLT2-I) have been proven to be cardio-protective when administered in cases of heart failure. This study intended to investigate the potential therapeutic effect of SGLT2-I on hyperthyroidism-related cardiopulmonary injury, targeting the possible underlying mechanisms. The impact of the SGLT2-I, dapagliflozin (DAPA), (1 mg/kg/day, p.o) on LT4 (0.3 mg/kg/day, i.p)-induced cardiopulmonary injury was investigated in rats. The body weight, ECG, and serum hormones were evaluated. Also, redox balance, DNA fragmentation, inflammatory cytokines, and PCR quantification in heart and lung tissues were employed to investigate the effect of DAPA in experimentally induced hyperthyroid rats along with histological and immunohistochemical examination. Coadministration of DAPA with LT4 effectively restored all serum biomarkers to nearly average levels, improved ECG findings, and reinstated the redox balance. Also, DAPA could improve DNA fragmentation, elevate mtTFA, and lessen TNF-α and IGF-1 gene expression in both organs of treated animals. Furthermore, DAPA markedly improved the necro-inflammatory and fibrotic cardiopulmonary histological alterations and reduced the tissue immunohistochemical expression of TNF-α and caspase-3. Although further clinical and deep molecular studies are required before transposing to humans, our study emphasized DAPA's potential to relieve hyperthyroidism-induced cardiopulmonary injury in rats through its antioxidant, anti-inflammatory, and anti-apoptotic effects, as well as via antagonizing the sympathetic over activity.

Excess Iodine Consumption Induces Oxidative Stress and Pancreatic Damage Independently of Chemical Form in Male Wistar Rats: Participation of PPAR-γ and C/EBP-β

BACKGROUND

Human beings consume different chemical forms of iodine in their diet. These are transported by different mechanisms in the cell. The forms of iodine can be part of thyroid hormones, bind to lipids, be an antioxidant, or be an oxidant, depending on their chemical form. The excessive consumption of iodine has been associated with pancreatic damage and diabetes mellitus type 2, but the association between disease and the chemical form consumed in the diet is unknown. This research analyzes the effect of excessive iodine consumption as Lugol (molecular iodine/potassium iodide solution) and iodate on parameters of pancreatic function, thyroid and lipid profiles, antioxidant and oxidant status, the expression of IR/Akt/P-Akt/GLUT4, and transcription factors PPAR-γ and CEBP-β.

METHODS

Three groups of Wistar rats were treated with 300 μg/L of iodine in drinking water: (1) control, (2) KIO3, and (3) Lugol.

RESULTS

Lugol and KIO3 consumption increased total iodine levels. Only KIO3 increased TSH levels. Both induced high serum glucose levels and increased oxidative stress and pancreatic alpha-amylase activity. Insulin levels and antioxidant status decreased significantly. PPAR-γ and C/EBP-β mRNA expression increased.

CONCLUSION

The pancreatic damage, hypertriglyceridemia, and oxidative stress were independent of the chemical form of iodine consumed. These effects depended on PPAR-γ, C/EBP-β, GLUT-4, and IR.

Neighborhood built environment, obesity, and diabetes: A Utah siblings study

Background

This study utilizes innovative computer vision methods alongside Google Street View images to characterize neighborhood built environments across Utah.

Methods

Convolutional Neural Networks were used to create indicators of street greenness, crosswalks, and building type on 1.4 million Google Street View images. The demographic and medical profiles of Utah residents came from the Utah Population Database (UPDB). We implemented hierarchical linear models with individuals nested within zip codes to estimate associations between neighborhood built environment features and individual-level obesity and diabetes, controlling for individual- and zip code-level characteristics (n = 1,899,175 adults living in Utah in 2015). Sibling random effects models were implemented to account for shared family attributes among siblings (n = 972,150) and twins (n = 14,122).

Results

Consistent with prior neighborhood research, the variance partition coefficients (VPC) of our unadjusted models nesting individuals within zip codes were relatively small (0.5%-5.3%), except for HbA1c (VPC = 23%), suggesting a small percentage of the outcome variance is at the zip code-level. However, proportional change in variance (PCV) attributable to zip codes after the inclusion of neighborhood built environment variables and covariates ranged between 11% and 67%, suggesting that these characteristics account for a substantial portion of the zip code-level effects. Non-single-family homes (indicator of mixed land use), sidewalks (indicator of walkability), and green streets (indicator of neighborhood aesthetics) were associated with reduced diabetes and obesity. Zip codes in the third tertile for non-single-family homes were associated with a 15% reduction (PR: 0.85; 95% CI: 0.79, 0.91) in obesity and a 20% reduction (PR: 0.80; 95% CI: 0.70, 0.91) in diabetes. This tertile was also associated with a BMI reduction of -0.68 kg/m2 (95% CI: -0.95, -0.40).

Conclusion

We observe associations between neighborhood characteristics and chronic diseases, accounting for biological, social, and cultural factors shared among siblings in this large population-based study.

Obesity and Obesity-Related Thyroid Dysfunction: Any Potential Role for the Very Low-Calorie Ketogenic Diet (VLCKD)?

PURPOSE OF REVIEW

This review aims to explore in-depth the different aspects of the association between very low-calorie ketogenic diet (VLCKD), obesity and obesity-related thyroid dysfunction.

RECENT FINDINGS

The VLCKD, proposed as a non-pharmacological strategy for the management of certain chronic diseases, is becoming increasingly popular worldwide. Initially used to treat epilepsy, it has been shown to be effective in controlling body weight gain and addressing various pathophysiological conditions. Research has shown that a low-calorie, high-fat diet can affect thyroid hormone levels. Weight loss can also influence thyroid hormone levels. Studies have suggested that long-term use of VLCKD for refractory epilepsy may be related to the development of hypothyroidism, with an effect seen in various populations. In particular, women with obesity following VLCKD tend to have reduced T3 levels. We propose further research to unravel the underlying mechanisms linking VLCKD to obesity and obesity-related thyroid dysfunction.

Urinary haloacetic acid concentrations and thyroid function among women: Results from the TREE study

BACKGROUND

Disinfection byproducts (DBPs) have been shown to impair thyroid function in experimental models. However, epidemiological evidence is scarce.

METHODS

This study included 1190 women undergoing assisted reproductive technology (ART) treatment from the Tongji Reproductive and Environmental (TREE) cohort from December 2018 to August 2021. Serum thyrotropin (TSH), free triiodothyronine (FT3), and free thyroxine (FT4) were measured as indicators of thyroid function. FT4/FT3 and TSH/FT4 ratios were calculated as markers of thyroid hormone homeostasis. Dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA), the two most abundant HAAs, in urine were detected to assess individual DBP exposures.

RESULTS

After adjusting for relevant covariates, positive associations were observed between urinary TCAA concentrations and serum TSH and TSH/FT4 levels (e.g., percent change = 5.82 %, 95 % CI: 0.70 %, 11.21 % for TSH), whereas inverse associations were found for serum FT3 and FT4 (e.g., percent change = -1.29 %, 95 % CI: -2.49 %, -0.07 % for FT3). There also was a negative association between urinary DCAA concentration and serum FT4/FT3 (percent change = -2.49 %, 95 % CI: -4.71 %, -0.23 %). These associations were further confirmed in the restricted cubic spline and generalized additive models with linear or U-shaped dose-response relationships.

CONCLUSION

Urinary HAAs were associated with altered thyroid hormone homeostasis among women undergoing ART treatment.

The Effect of Mediterranean Diet on Thyroid Gland Activity

The main goal of this research was to determine whether there is a correlation between adherence to the Mediterranean diet (assessed by the Mediterranean Diet Serving Score (MDSS)) and parameters indicating thyroid gland activity, such as concentration of thyroid-stimulating hormone (TSH), thyroid hormones (free triiodothyronine (fT3), free thyroxine (fT4)), thyroglobulin (Tg), antibodies to thyroid proteins (thyroglobulin antibodies (TgAb) and thyroid peroxidase antibodies (TPOAb)), and calcitonin (CT) in plasma and serum samples. An additional objective was to investigate whether there are differences in the values of the MDSS among clinical groups (euthyroid individuals, euthyroid individuals with positive TgAb and/or TPOAb, and hypothyroid and hyperthyroid participants). This cross-sectional study included 4620 participants over 18 years of age from the islands of Korčula and Vis, and the mainland city of Split. The MDSS was assessed from a food frequency questionnaire (FFQ). MDSS values were significantly higher in females compared to males and showed a positive association with the age of the participants. There was no significant difference in the MDSS values among the examined clinical groups. In the group of subjects with euthyroidism, a significant positive association was found between fT3 and the MDSS, while in the group of subjects with subclinical hypothyroidism, a significant positive association was observed between the MDSS and both fT3 and fT4. CT levels were also positively associated with the MDSS. Considering the significant positive association of the MDSS and both fT3 and fT4 levels in patients with subclinical hypothyroidism, the results of this study could be used to create guidelines for selecting an appropriate, potentially protective diet for these patients.

Effective substances and molecular mechanisms guided by network pharmacology: An example study of Scrophulariae Radix treatment of hyperthyroidism and thyroid hormone-induced liver and kidney injuries

ETHNOPHARMACOLOGICAL RELEVANCE

Scrophulariae Radix (Xuanshen [XS]) has been used for several years to treat hyperthyroidism. However, its effective substances and pharmacological mechanisms in the treatment of hyperthyroidism and thyroid hormone-induced liver and kidney injuries have not yet been elucidated.

AIM OF THE STUDY

This study aimed to explore the pharmacological material basis and potential mechanism of XS therapy for hyperthyroidism and thyroid hormone-induced liver and kidney injuries based on network pharmacology prediction and experimental validation.

MATERIALS AND METHODS

Based on 31 in vivo XS compounds identified using ultra-performance liquid chromatography tandem quadruple exactive orbitrap high-resolution accurate-mass spectrometry (UPLC-QE-HRMS), a network pharmacology approach was used for mechanism prediction. Systematic networks were constructed to identify the potential molecular targets, biological processes (BP), and signaling pathways. A component-target-pathway network was established. Mice were administered levothyroxine sodium through gavage for 30 d and then treated with different doses of XS extract with or without propylthiouracil (PTU) for 30 d. Blood, liver, and kidney samples were analyzed using an enzyme-linked immunosorbent assay (ELISA) and western blotting.

RESULTS

A total of 31 prototypes, 60 Phase I metabolites, and 23 Phase II metabolites were tentatively identified in the plasma of rats following the oral administration of XS extract. Ninety-six potential common targets between the 31 in vivo compounds and the diseases were identified. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that Bcl-2, BAD, JNK, p38, and ERK1/2 were the top targets. XS extract with or without PTU had the following effects: inhibition of T3/T4/fT3/fT4 caused by levothyroxine; increase of TSH levels in serum; restoration of thyroid structure; improvement of liver and kidney structure and function by elevating the activities of anti-oxidant enzymes catalase (CAT),superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px); activation anti-apoptotic proteins Bcl-2; inhibition the apoptotic protein p-BAD; downregulation inflammation-related proteins p-ERK1/2, p-JNK, and p-p38; and inhibition of the aggregation of pro-inflammatory cytokines TNF-α, IL-1β, and IL-6, as well as immune cells in the liver.

CONCLUSION

XS can be used to treat hyperthyroidism and liver and kidney injuries caused by thyroid hormones through its anti-oxidant, anti-inflammatory, and anti-apoptotic properties. In addition, serum pharmacochemical analysis revealed that five active compounds, namely 4-methylcatechol, sugiol, eugenol, acetovanillone, and oleic acid, have diverse metabolic pathways in vivo and exhibit potential as effective therapeutic agents.

The relationship between dietary total flavonoids and thyroid function in U.S.adults, NHANES 2007-2010

BACKGROUND

Although small studies have shown that flavonoids can affect thyroid disease, few epidemiological studies have explored the relationship between dietary total flavonoids (TFs) intake and serum thyroid function. The aim of this research was to evaluate the relationship between TFs and serum thyroid function.

METHODS

Our study included 4,949 adults from the National Health and Nutrition Examination Survey (NHANES) 2007-2010. Multivariable linear regression, subgroup analyses, and interaction terms were used to explore the relationships between TFs and thyroid function. And we also used restricted cubic splines (RCS) to investigate possible nonlinear relationships.

RESULTS

After adjusting for covariates, we found that log10-transformated dietary total flavonoids intake (LgTFs) was negatively associated with total thyroxine (TT4) (β = -0.153, 95% CI = -0.222 to -0.084, P<0.001). Subgroup analyses revealed a stronger and statistically supported association in subjects with high annual family income (β = -0.367, P<0.001, P for interaction = 0.026) and subjects with high poverty to income ratio (PIR) (β = -0.622, P<0.001, P for interaction = 0.042). And we found a U-shaped curve association between LgTFs and free triiodothyronine (FT3) (inflection point for LgTFs: 2.063).

CONCLUSION

The results of our study demonstrated that a higher intake of total flavonoids in the diet was negatively associated with a lower TT4. Furthermore, the associations were more pronounced in high annual family income and high PIR adults. And we found a U-shaped relationship between LgTFs and FT3. These findings provided guidance for future thyroid dysfunction diet guidelines.

Serum klotho associated with thyroid hormone in adults: A population-based cross-sectional research

BACKGROUND AND STUDY AIM

The klotho protein, a multifunctional protein, has been shown to be associated with a wide range of endocrine diseases and has been linked to thyroid tumourigenesis. However, the relationship between serum klotho levels and thyroid hormones remains poorly understood. This study aimed to explore the correlation between serum klotho levels and thyroid hormones.

METHODS

Data was obtained from the NHANES cycles 2007-2008, 2009-2010, and 2011-2012. A total of 4674 participants were recruited for this study. Statistical analysis was using multiple linear regression analyses, and restricted cubic spline plots (RCS) to investigate the association between serum klotho levels and serum levels of thyroid hormones.

RESULTS

In the unadjusted covariate model, ln(klotho) significantly positively correlated with tT3, tT4, fT3, tT4/fT4, and tT3/fT3 (all P<0.01) and negatively correlated with TSH, tT4/tT3, and fT4/fT3 (all P<0.05). Furthermore, tT3, tT4, fT3and tT3/fT3 (P < 0.05) were still significant in the adjusted model. And it is worth noting that there is an approximately L-shaped nonlinear relationship between ln(klotho) and fT3,tT3 with a cut-off point of 6.697 (P-non-linear < 0.05). The stratification analysis showed gender and iodine level differences in the relationship between serum Klotho levels and thyroid hormones.

CONCLUSION

There is an L-shaped nonlinear relationship between ln(klotho) and fT3, tT3, suggesting that klotho could be involved in the physiological regulation of thyroid function.

Prevalence of thyroid dysfunction and associated factors among adult type 2 diabetes mellitus patients, 2000-2022: a systematic review and meta-analysis

BACKGROUND

Thyroid dysfunction (TD) and type 2 diabetes mellitus (T2DM) frequently co-occur and have overlapping pathologies, and their risk increases with age. Thyroid dysfunction along with T2DM will worsen macro- and microvascular complications, morbidity, and mortality.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement guideline was followed. The databases used were Embase, ScienceDirect, PubMed, and Google Scholar. The Joana Briggs Institute (JBI) scale was used to assess the quality of the included studies. The data was extracted by Microsoft Excel and analyzed through STATA version 14 software. The overall pooled prevalence of TD and its main components were estimated using the random-effects model. The consistency of studies was assessed by I2 test statistics. Pooled meta-logistic regression was used to present the pooled prevalence with a 95% confidence interval (CI). Besides, subgroup and sensitivity analyses were employed.

RESULT

Thirty-eight studies were included. The pooled prevalence of TD was 20.24% (95% CI: 17.85, 22.64). The pooled prevalence of subclinical hypothyroidism, hypothyroidism, subclinical hyperthyroidism, and hyperthyroidism was found to be 11.87% (95% CI: 6.90, 16.84), 7.75% (95% CI: 5.71, 9.79), 2.49% (95% CI: 0.73, 4.25), and 2.51% (95% CI: 1.89, 3.13), respectively. Subgroup analysis based on continent revealed a higher prevalence of TD in Asia and Africa. Factors like being female, HbA1c ≥ 7%, DM duration > 5 years, family history of TD, central obesity, smoking, the presence of retinopathy, and neuropathy were found associated with TD.

CONCLUSION

The current systematic review and meta-analysis showed that the TD's pooled prevalence was relatively higher than the general population. Therefore, regular screening of TD should be done for T2DM patients.

Exploring oral drug delivery: In vitro release and mathematical modeling of hydrophobic drug (Na-L-thyroxine) and its cyclodextrin inclusion complex in chitosan microparticles

Na-l-Thyroxine (Na-l-Thy) is a frequently prescribed synthetic hormone for hypothyroidism treatment. Despite its efficacy, its hydrophobic nature poses a challenge for achieving optimal bioavailability. To address this, researchers explored various delivery methods, including micro-formulations and nano-formulations, for precise and prolonged release of hydrophobic and hydrophilic drugs. In this study, we developed micro-formulations with cyclodextrin and chitosan. Docking studies identified γ-cyclodextrin as the preferred option for forming a stable complex with Na-l-Thyroxine compared to α, and β-cyclodextrins. Two micro-formulations were prepared compared: Na-l-Thyroxine loaded on chitosan (CS + Na-l-Thy) and Na-l-Thyroxine and γ-cyclodextrin inclusion complex (IC) loaded on chitosan (CS + IC). CS + IC exhibited superior encapsulation efficiency (91.25 %) and loading capacity (18.62 %) compared to CS + Na-l-Thy (encapsulation efficiency: 70.24 %, loading capacity: 21.18 %). Characterization using FTIR, SEM, and TGA validated successful encapsulation of Na-l-Thy in spherical microparticles with high thermal stability. In-vitro release studies at pH 1.2 and 7.4 showed that the CS + IC microparticles displayed gradual, consistent drug release compared to CS + Na-l-Thy -Thy. Both formulations showed faster release at pH 1.2 than at pH 7.4. Reaction kinetics analysis of release studies of CS + Na-l-Thy and CS + IC were best described by Higuchi kinetic model and Korsemeyer-Peppas kinetic model respectively. This study suggests that the CS + IC microparticles are an effective and stable delivery system for sustained release of hydrophobic Na-l-Thy.

Impact of methimazole-induced hypothyroidism on postnatal swine

Thyroid hormones regulate metabolic rate, nutrient utilization, growth, and development. Swine are susceptible to thyroid suppression in response to disease or environmental conditions, but the physiological impact of such disruption has not been established. The objective of this study was to evaluate the impact of hypothyroidism induced with the antithyroid medication methimazole (MMI). 10 mg/kg MMI significantly decreased circulating triiodothyronine (T3) for the duration of treatment but had only a transient effect on circulating thyroxine (T4). Thyroid tissue weight was significantly increased by more than 3.5-fold in response to MMI treatment. Histologically, the eosinophilic colloid was largely absent from the thyroid follicle which displayed a disorganized columnar epithelium consistent with goiter. MMI induced hypothyroidism has no effect on growth rate over 28 days. Hepatic expression of genes associated with thyroid metabolism (DIO1, DIO2, and DIO3), lipid utilization (CD36, FASN, and ACACA), apoptosis (TP53, PERP, SIVA1, and SFN) and proliferation (CDK1, CDK2, CDK4, and CDKN1A) were unaffected by treatment. Collectively these results demonstrate that MMI induces mild systemic hypothyroidism and pronounced goiter, indicating a strong homeostatic central regulation within the hypothalamic pituitary thyroid axis. This combined with limited peripheral effects, indicates resilience to hypothyroidism in modern swine.

Prenatal double-hit with aluminium and cadmium mediate testicular atrophy and hypothalamic hypoplasia: the role of oxido-nitrergic stress and endocrine perturbations

There is limited experimental evidence on the biochemical consequences of aluminium (Al) and cadmium (Cd) co-exposures during pregnancy and postnatal life.This study investigated the impacts of perinatal Al chloride (AlCl3) and Cd chloride (CdCl2) co-exposures on neuroendocrine functions in mice offspring during postnatal life. The study comprised of four pregnant experimental groups. Group 1 received AlCl3 (10 mg/kg), group 2 were administered CdCl2 (1.5 mg/kg), while group 3 received both AlCl3 (10 mg/kg) and CdCl2 (1.5 mg/kg) (AlCl3+CdCl2), and group 4 received saline (10 mL/kg) only and served as control group. All experimental animals were chemically exposed once daily from gestation days 7-20. Upon delivery, male pups were regrouped based on maternal chemical exposure on postnatal day 21 (PND 21) and allowed to grow to adulthood until PND 78, after which they were sacrificed for assessment of neuroendocrine markers and histological investigations. There was no statistical significance (p > 0.05) on follicle stimulating hormone, testosterone, estrogen and progesterone, thyroid stimulating hormone, thyroxine (T4) in all treatment groups relative to controls|. However, AlCl3 and AlCl3-CdCl2 significantly (p < 0.05) reduced triiodothyronine (T3) levels, with a profound increase in T3:T4 ratio by AlCl3, and AlCl3+CdCl2 compared to control. Furthermore, pups from pregnant mice treated with CdCl2 and AlCl3+CdCl2 demonstrated increased testicular malondialdehyde concentration with increased catalase activity relative to controls, suggesting oxidative imbalance. In addition, AlCl3, CdCl2, and AlCl3+CdCl2 exposures induced testicular and hypothalamic architectural disruption compared to controls, with marked architectural derangement in the AlCl3+CdCl2 group. Our findings suggest that prenatal co-exposures to Alcl3 and CdCl2 induce testicular and hypothalamic alterations in offspring via a testicular oxidative stress and thyrotoxicosis-dependent mechanisms.

Effect of Ramadan fasting on thyroid functions in hypothyroid patients taking levothyroxine: a systematic review and meta-analysis

BACKGROUND

The major changes in the timing of meals during Ramadan may be challenging for hypothyroid patients on levothyroxine. We aimed to study the effect of Ramadan fasting on thyroid functions in hypothyroid patients taking levothyroxine.

METHODS

We did a comprehensive search of 8 databases for Randomized controlled studies (RCTs) and observational studies investigating the effect of Ramadan fasting on thyroid functions in hypothyroid individuals taking levothyroxine. Relevant data was extracted and analyzed. Mean difference (MD) and standard deviation (SD) were used to evaluate the continuous data. Risk ratios (RR) with a 95% confidence interval were used for outcomes constituting dichotomous data. National Institutes of Health (NIH) tools were used to assess the risk of bias.

RESULTS

Fourteen studies met our inclusion criteria, 3 RCTs, and 11 observational studies, all designed as pre-post studies. Ramadan fasting was associated with a statistically significant increase in TSH in patients who were euthyroid before Ramadan (MD = -0.76 [95% CI; -1.27, -0.25]). However, free thyroxine (FT4) was found to be stable (MD = 0.01, [95% CI; -0.03, 0.06]). All timing points were associated with a significant increase in TSH levels after Ramadan, pre-iftar (MD = -0.69 [95% CI; -1.03, -0.36]), post-iftar (MD = -0.76 [95% CI; -1.12, -0.39]), and pre-suhoor (MD = -1.19 [95% CI; -2.18, -0.19]).

CONCLUSION

TSH increases significantly after Ramadan. No timing point has superiority in maintaining thyroid control. However, choosing the timing should be individualized according to the patient's preference to guarantee the most possible compliance.

The possible impacts of nano and microplastics on human health: lessons from experimental models across multiple organs

The widespread production and use of plastics have resulted in accumulation of plastic debris in the environment, gradually breaking down into smaller particles over time. Nano-plastics (NPs) and microplastics (MPs), defined as particles smaller than 100 nanometers and 5 millimeters, respectively, raise concerns due to their ability to enter the human body through various pathways including ingestion, inhalation, and skin contact. Various investigators demonstrated that these particles may produce physical and chemical damage to human cells, tissues, and organs, disrupting cellular processes, triggering inflammation and oxidative stress, and impacting hormone and neurotransmitter balance. In addition, micro- and nano-plastics (MNPLs) may carry toxic chemicals and pathogens, exacerbating adverse effects on human health. The magnitude and nature of these effects are not yet fully understood, requiring further research for a comprehensive risk assessment. Nevertheless, evidence available suggests that accumulation of these particles in the environment and potential human uptake are causes for concern. Urgent measures to reduce plastic pollution and limit human exposure to MNPLs are necessary to safeguard human health and the environment. In this review, current knowledge regarding the influence of MNPLs on human health is summarized, including toxicity mechanisms, exposure pathways, and health outcomes across multiple organs. The critical need for additional research is also emphasized to comprehensively assess potential risks posed by degradation of MNPLs on human health and inform strategies for addressing this emerging environmental health challenge. Finally, new research directions are proposed including evaluation of gene regulation associated with MNPLs exposure.

The crosstalk between benign thyroid disease and breast cancer: A single center study

This study aims to investigate the relationship between benign thyroid disease and breast cancer. The clinical study includes a total of 600 participants, divided into 2 groups: the control group (N = 300), which consists of individuals from the checkup population during the same periods, and the experimental group (N = 300), which consists of patients with breast cancer. General data of the participants, including age, tumor diameter, tumor staging, pathological classification, lymph node metastasis, and classification of benign thyroid disease, were collected and analyzed. The levels of TT3, TT4, FT3, FT4, TSH, TPOAb, and TgAb in blood samples from the experimental and control groups were determined using a radioimmune method. The levels of TPOAb, TgAb, and TSH in the experimental group were significantly higher than those in the control group, while the levels of TT3, TT4, FT3, and FT4 in the experimental group were significantly lower. The general data of the participants contributed to the appropriate sample size and allocation. Furthermore, benign thyroid disease contributes to the development of breast cancer by regulating the levels of TT3, TT4, FT3, FT4, TSH, TPOAb, and TgAb.

The multi-faceted nature of age-associated osteoporosis

Age-associated osteoporosis (AAOP) poses a significant health burden, characterized by increased fracture risk due to declining bone mass and strength. Effective prevention and early treatment strategies are crucial to mitigate the disease burden and the associated healthcare costs. Current therapeutic approaches effectively target the individual contributing factors to AAOP. Nonetheless, the management of AAOP is complicated by the multitude of variables that affect its development. Main intrinsic and extrinsic factors contributing to AAOP risk are reviewed here, including mechanical unloading, nutrient deficiency, hormonal disbalance, disrupted metabolism, cognitive decline, inflammation and circadian disruption. Furthermore, it is discussed how these can be targeted for prevention and treatment. Although valuable as individual targets for intervention, the interconnectedness of these risk factors result in a unique etiology for every patient. Acknowledgement of the multifaceted nature of AAOP will enable the development of more effective and sustainable management strategies, based on a holistic, patient-centered approach.

Histological evidence of hypothyroidism in mice chronically exposed to conventional farming

Worldwide, disorders of the thyroid gland are a growing concern; such can be caused by exposure to contaminants, including agrochemicals used in conventional agriculture, which act as endocrine disruptors. The purpose of this study is to evaluate whether or not exposure to an environment with conventional agriculture leads to thyroid disruption. Mus musculus were used as bioindicator species, captured in two sites: a farm where conventional agriculture is practiced, and a place without agriculture. Thyroid histomorphometric and morphologic data were analyzed. The impacts of the agricultural environment over the thyroid were revealed, as indications of hypothyroidism were observed in exposed mice: the area and volume of epithelial cells were much lower. Alterations in thyroid histomorphology were also observed: lower follicular sphericity, irregularly delimited epithelium and increased exfoliation into the colloid. These results highlight the need for transition from current conventional agricultural systems towards organic systems.

Assessment of Individual and Mixed Effects of Six Minerals on Thyroid Hormones in Chinese Pregnant Women

The biosynthesis of thyroid hormones is essential for brain and neurological development. It requires iodine as a key component but is also influenced by other nutrients. Evidence for the combined nutrient status in relation to thyroid hormones during pregnancy is limited. We aimed to investigate the joint associations of iodine, selenium, zinc, calcium, magnesium and iron with maternal thyroid functions in 489 pregnant women from Hangzhou, China. Serum levels of six essential minerals and thyroid function parameters were measured during the first antenatal visit. Linear regression, quantile g-computation and Bayesian kernel machine regression were used to explore the individual and joint relationships between the six minerals and thyroid hormones. Linear regression analyses revealed that calcium was positively associated with free triiodothyronine (FT3). Zinc was positively associated with free thyroxine (FT4). Iodine was negatively associated with thyroid-stimulating hormone (TSH) and positively associated with FT3 and FT4. The quantile g-computation and BKMR models indicated that the joint nutrient concentration was negatively associated with TSH and positively associated with FT3 and FT4. Among the six minerals, iodine contributed most to thyroid function. The findings suggested that maintaining the appropriate concentration of minerals, either as individuals or a mixture, is important for thyroid health during pregnancy.

Total weight loss induces the alteration in thyroid function after bariatric surgery

Background

Bariatric surgery is an effective approach to weight loss, which may also affect thyroid function. However, alteration in thyroid-stimulating hormone (ΔTSH) and thyroid hormones after bariatric surgery and the relationship between thyroid function and postoperative weight loss still remains controversial.

Methods

Data were collected from euthyroid patients with obesity who underwent sleeve gastrectomy and Roux-en-Y gastric bypass from 2017 to 2022. The alterations of free thyroxine (FT4), free triiodothyronine (FT3), total thyroxine (TT4), total triiodothyronine (TT3), and TSH were calculated 1 year after surgery. Pearson correlation analysis was used to assess the correlation between the percentage of total weight loss (%TWL) and ΔTSH. Multivariable linear regression was utilized to determine the association between %TWL and ΔTSH.

Results

A total of 256 patients were included in our study. The mean %TWL was 28.29% after 1 year. TSH decreased from 2.33 (1.67, 3.04) uIU/mL to 1.82 (1.21, 2.50) uIU/mL (P < 0.001), FT3 decreased from 3.23 ± 0.42 pg/mL to 2.89 ± 0.41 pg/mL (P < 0.001), FT4 decreased from 1.11 ± 0.25 ng/dL to 1.02 ± 0.25 ng/dL (P < 0.001), TT3 decreased from 1.13 (1.00, 1.25) ng/mL to 0.89 (0.78, 1.00) ng/mL (P < 0.001), and TT4 decreased from 8.28 ± 1.69 ug/mL to 7.82 ± 1.68 ug/mL 1 year postoperatively (P < 0.001). %TWL was found to be significantly correlated to ΔTSH by Pearson correlation analysis (Pearson correlation coefficient = 0.184, P = 0.003), indicating that the more weight loss, the more TSH declined. After adjusting for covariates in multivariable linear regression, %TWL was found to be independently associated with ΔTSH (β = 0.180 [95% confidence interval (CI), 0.048 - 0.312], P = 0.008). Moreover, %TWL was divided into 3 categorical groups (%TWL ≤ 25%, 25% < %TWL ≤ 35%, and %TWL > 35%) for further exploration, and was also found to be an independent predictor for ΔTSH after adjusting for covariates in multivariable linear regression (β = 0.153 [95% CI, 0.019 - 0.287], P = 0.025).

Conclusion

TSH, FT4, FT3, TT4, and TT3 decrease significantly 1 year after bariatric surgery. The decline in TSH is independently mediated by postoperative weight loss; the more the weight loss, the more the TSH decrease.

Effects of altitude on thyroid disorders according to Chinese three-rung, ladder-like topography: national cross-sectional study

BACKGROUND

Chinese topography appears a three-rung ladder-like distribution of decreasing elevation from northwest to southeast, which is divided by two sloping edges. Previous studies have reported that prevalence of thyroid diseases differed by altitude, and geographical factors were associated with thyroid disorders. To explore the association between three-rung ladder-like regions and thyroid disorders according to unique Chinese topographic features, we conducted an epidemiological cross-sectional study from 2015-2017 that covered all 31 mainland Chinese provinces.

METHODS

A total of 78,470 participants aged ≥ 18 years from a nationally representative cross-sectional study were included. Serum thyroid peroxidase antibody, thyroglobulin antibody, and thyroid-stimulating hormone levels; urine iodine concentration; and thyroid volume were measured. The three-rung ladder-like distribution of decreasing elevation from northwest to southeast in China was categorized into three topographic groups according to elevation: first ladder, > 3000 m above sea level; second ladder, descending from 3000-500 m; and third ladder, descending from 500 m to sea level. The third ladder was further divided into groups A (500-100 m) and B (< 100 m). Associations between geographic factors and thyroid disorders were assessed using linear and binary logistic regression analyses.

RESULTS

Participants in the first ladder group were associated with lower thyroid peroxidase (β = -4.69; P = 0.00), thyroglobulin antibody levels (β = -11.08; P = 0.01), and the largest thyroid volume (β = 1.74; P = 0.00), compared with the other groups. The second ladder group was associated with autoimmune thyroiditis (odds ratio = 1.30, 95% confidence interval [1.18-1.43]) and subclinical hypothyroidism (odds ratio = 0.61, 95%confidence interval [0.57-0.66]) (P < 0.05) compared with the first ladder group. Group A (third ladder) (500-100 m) was associated with thyroid nodules and subclinical hypothyroidism (P < 0.05). Furthermore, group B (< 100 m) was positively associated with autoimmune thyroiditis, thyroid peroxidase and thyroglobulin antibody positivity, and negatively associated with overt hypothyroidism, subclinical hypothyroidism, and goiter compared with the first ladder group(P < 0.05).

CONCLUSION

We are the first to investigate the association between different ladder regions and thyroid disorders according to unique Chinese topographic features. The prevalence of thyroid disorders varied among the three-rung ladder-like topography groups in China, with the exception of overt hyperthyroidism.

Factors responsible for the persistence of Hypothyroidism among Pakistani Women

Substantial change in climate over the years in South Asia is directly affecting the diet and health of the population. It is important to analyze the aftermath of this change and its impact on the thyroid status. In recent years, a complex interplay of the changing climate with the environmental, geographical and dietary factors has contributed to the continued prevalence of hypothyroidism in Pakistani women. To study the influence of various factors which might be aggravating hypothyroidism in the female population of Pakistan, a thorough search of literature was conducted of various databases including Google Scholar and PubMed. Google as a search engine was also explored. This included both interventional and observational studies, published in English, from the year 1950 onwards uptil June 2023. It also included WHO website and local news clips about the awareness campaigns on iodine deficiency over the past years. All studies conducted on females to diagnose hypothyroidism, with both positive and negative outcomes were included in this study. The factors contributing to hypothyroidism among the female population in Pakistan encompass the effects of climate change, both direct and indirect, topographical factor, indiscriminate use of hazardous pesticides, presence of chemical contaminants in food and water, and a lack of awareness among the public and healthcare professionals about the condition's symptoms and management.

Cardiometabolic-related dietary patterns and thyroid function: a population-based cross-sectional study

BACKGROUND

Little is known about the association of dietary patterns with thyroid function. Since thyroid function and cardiometabolic variables are inter-related, we investigated whether cardiometabolic-related dietary patterns are associated with thyroid function.

METHODS

This cross-sectional study included 3520 Tehran Lipid and Glucose Study participants. Reduced rank regression was used to find dietary patterns with body mass index, serum fasting glucose, triglycerides, HDL-C, and systolic and diastolic blood pressures as response variables. Two patterns were retained, one based on 35 food groups (native-based pattern) and the other based on the European Prospective Investigation into Cancer and Nutrition Germany (EPIC) food grouping (n = 33). A confirmatory cardio-metabolic dietary pattern was also created according to the weight of food groups proposed by the Framingham Offspring Study (FOS). The association of each pattern with thyroid-stimulating hormone (TSH), free thyroxine, and thyroid peroxidase antibody (TPOAb) and the odds of thyroid dysfunction was examined by linear and logistic regression, respectively.

RESULTS

The two exploratory dietary patterns were highly correlated and associated with greater TSH levels in euthyroid participants. The adjusted odds ratio (95% CI) of subclinical hypothyroidism per one standard deviation was 1.14 (1.01, 1.28) for the native-based pattern and 1.16 (1.03, 1.31) for the EPIC-based pattern. The odds of subclinical hypothyroidism was significantly greater in the second and third tertiles of the native-based pattern compared to the first tertile in the adjusted model (p-trend = 0.005). The odds of subclinical hypothyroidism increased across the tertiles of the EPIC-based pattern, but the odds was significantly higher only in tertile 3 compared to tertile 1, with an OR (95% CI) of 1.44 (1.07, 1.94) in the adjusted model. The adjusted odds of clinical hypothyroidism were greater in tertile 3 of the native-based pattern compared with tertile 1 (OR = 1.65, 95% CI 1.04, 2.62). The patterns were unrelated to hyperthyroidism or TPOAb positivity. The FOS-based confirmatory score was unrelated to thyroid function.

CONCLUSIONS

A diet high in fast foods, soft drinks, and legumes and low in confectionery, potatoes, butter, and jam and honey was associated with higher TSH levels in euthyroidism and higher odds of subclinical hypothyroidism.

Associations of Urinary Phthalate Metabolites with Thyroid Function and the Mediated Role of Cytokines: A Panel Study of Healthy Children

Evidence on joint association of a phthalate mixture with thyroid function among children and its underlying mechanism is largely unknown. We aimed to explore the associations of 10 urinary phthalate metabolites (mPAEs), either as individuals or as a mixture, with thyroid function indicators [free thyroxine, free triiodothyronine (FT3), and thyroid-stimulating hormone (TSH)] in 144 children aged 4-12 years with up to 3 repeated visits across 3 seasons. Significant and positive associations were observed for mono-(2-ethylhexyl) phthalate (MEHP), mono-iso-butyl phthalate (MiBP), and mono-n-butyl phthalate (MnBP) with TSH, as well as monobenzyl phthalate (MBzP) with FT3 in dose-response manners. The relationship between MEHP and TSH remained robust in multiple-phthalate models. Bayesian kernel machine regression (BKMR) models revealed overall linear associations of the 10 mPAE mixture with higher TSH and FT3 levels, and MEHP and MBzP were major contributors. Meanwhile, MEHP, MiBP, and MnBP were linked to the elevation of multiple cytokines including CCL 27, CCL3, CXCL1, and IL-16. Among them, IL-16 mediated the relationships of MEHP and MiBP with TSH, and the mediated proportions were 24.16% and 24.27%, respectively. Our findings suggested that mPAEs dominated by MEHP were dose-responsively associated with elevated TSH among healthy children and mediated by IL-16.

Association between the Systemic Immune-Inflammation Index and Thyroid Function in U.S. Adults

Background

The systemic immune-inflammation index (SII) is used as an indicator of prognosis for a wide range of diseases. Thyroid function has been found to be strongly associated with inflammation. The purpose of this investigation was to analyze the correlation between SII and various thyroid functions.

Methods

This study utilized data from the National Health and Nutrition Examination Survey (NHANES) 2007-2012. The association between SII and thyroid function was analyzed using weighted univariate and multivariate linear regression analyses. Subgroup analyses, interaction tests, and weighted restricted cubic spline (RCS) regression analyses were also employed to test this correlation.

Results

Of the 6,875 participants (age ≥ 20 years), the mean age was 46.87 ± 0.40 years. The adjusted model showed that lnSII was negatively correlated with FT3 (β = -0.0559, 95% CI -0.1060 to -0.0059,) and FT3/FT4 (β = -0.0920, 95% CI -0.1667 to -0.0173,). There was a positive correlation between lnSII and TT4 (β = 0.1499, 95% CI 0.0722-0.2276,). In subgroup analyses, lnSII still independently affected a wide range of thyroid functions. Weighted RCS analysis showed a nonlinear relationship between FT3 and lnSII.

Conclusion

Close relationships exist between SII and a variety of thyroid functions. SII can be used as an indicator to predict thyroid dysfunction. Control of inflammatory activity may be a protective measure against thyroid dysfunction. More large-scale prospective studies are necessary to further explore the correlation between SII and thyroid function and the role of obesity in this.

In-silico studies of Brassica oleracea active compounds and their role in thyroid peroxidase activity

Cabbage, a leafy vegetable that is widely consumed across the globe, holds a significant place within the Brassica family. For almost a century, its potential anti-thyroid effects have captured attention. The presence of compounds such as thiocyanate and goitrin in cabbage has been extensively investigated for their ability to impede sodium-iodide symporter and thyroid peroxidase (TPO) activities. The present study is focused on uncovering the active constituents in cabbage that could interact with TPO, while also examining their stability under cooking temperatures. Employing molecular docking and molecular dynamic simulation techniques, we quantified the binding strength of phytochemicals present in cabbage with the target. Out of the 60 compounds identified in cabbage leaves, only 18 exhibited docking scores surpassing those of the commercially available anti-thyroid drug, methimazole. These chosen compounds were studied for binding free energy and pharmacokinetic properties. A specific compound, gamma-Terpinene, classified as a monoterpene, emerged as noteworthy due to its alignment with all criteria and the highest observed binding free energy compared to others. Furthermore, we explored the stability of gamma-Terpinene at 373.15K (cooking temperature) and observed its susceptibility to degradation. This might contribute to the relatively diminished anti-thyroid effects of cabbage when consumed in cooked form. Consequently, our findings suggest that the consumption of cooked cabbage could be more conducive to maintaining normal thyroid function, as opposed to its raw counterpart.Communicated by Ramaswamy H. Sarma.

Relationship between gut microbiota and thyroid function: a two-sample Mendelian randomization study

Background

Numerous observational studies have indicated a link between the composition of gut microbiota and thyroid function. Nevertheless, the precise causal relationship between gut microbiota and thyroid function remains uncertain.

Methods

In this two-sample Mendelian randomization study, we utilized summary data from a genome-wide association study of gut microbiota composition in 18,340 participants from 24 cohorts, as well as summary statistics on thyroid hormones and thyroid-stimulating hormone from the ThyroidOmics Consortium and summary statistics on hypothyroidism and hyperthyroidism from the FinnGen R8 release. Five different methods, including inverse variance weighting, MR-Egger, weighted median, weighted mode, and simple mode, were employed to examine the causal relationship between gut microbiota and thyroid function. Reverse Mendelian randomization analysis was conducted for taxa identified as having a causal relationship with thyroid function in the Mendelian randomization analysis. To assess the robustness of the results, sensitivity analyses were conducted employing Cochran's Q test, MR-Egger intercept test, MR-PRESSO global test, and leave-one-out analysis.

Results

Through MR analysis of 211 microbial taxa and 4 phenotypes, we identified a total of 34 gut microbiota taxa that were associated with the outcomes. After using the bonferroni method for multiple testing correction, phylum Actinobacteria (id.400) had a protective effect on hypothyroidism (OR=0.883, 95% CI: 0.817-0.955, P=0.002), and class Deltaproteobacteria (id.3087) had a protective effect on hyperthyroidism (OR=0.549, 95% CI: 0.374-0.805, P=0.002). According to the results of reverse MR analysis, no significant causal effect of the four phenotypes was found on gut microbiota. No significant horizontal pleiotropy was detected based on MR-Egger intercept test and MR-PRESSO global test.

Conclusion

Through two-sample MR analysis, we identified specific gut microbiota taxa at the genetic level that are predicted to have a causal relationship with thyroid function, which may serve as useful biomarkers for early disease diagnosis.

The benefits of rehabilitation exercise in improving chronic traumatic encephalopathy: recent advances and future perspectives

Traumatic encephalopathy syndrome (TES) is used to describe the clinical manifestations of chronic traumatic encephalopathy (CTE). However, effective treatment and prevention strategies are lacking. Increasing evidence has shown that rehabilitation training could prevent cognitive decline, enhance brain plasticity, and effectively improve neurological function in neurodegenerative diseases. Therefore, the mechanisms involved in the effects of rehabilitation exercise therapy on the prognosis of CTE are worth exploring. The aim of this article is to review the pathogenesis of CTE and provide a potential clinical intervention strategy for CTE.

Nickel as a potential disruptor of thyroid function: benchmark modelling of human data

Introduction

Nickel (Ni) is one of the well-known toxic metals found in the environment. However, its influence on thyroid function is not explored enough. Hence, the aim of this study was to analyse the potential of Ni to disrupt thyroid function by exploring the relationship between blood Ni concentration and serum hormone levels (TSH, T4, T3, fT4 and fT3), as well as the parameters of thyroid homeostasis (SPINA-GT and SPINA-GD) by using correlation analysis and Benchmark (BMD) concept.

Methods

Ni concentration was measured by ICP-MS method, while CLIA was used for serum hormone determination. SPINA Thyr software was used to calculate SPINA-GT and SPINA-GD parameters. BMD analysis was performed by PROAST software (70.1). The limitations of this study are the small sample size and the uneven distribution of healthy and unhealthy subjects, limited confounding factors, as well as the age of the subjects that could have influenced the obtained results.

Results and discussion

The highest median value for blood Ni concentration was observed for the male population and amounted 8,278 µg/L. Accordingly, the statistically significant correlation was observed only in the male population, for Ni-fT4 and Ni-SPINA-GT pairs. The existence of a dose-response relationship was established between Ni and all the measured parameters of thyroid functions in entire population and in both sexes. However, the narrowest BMD intervals were obtained only in men, for Ni - SPINA-GT pair (1.36-60.9 µg/L) and Ni - fT3 pair (0.397-66.8 µg/L), indicating that even 78.68 and 83.25% of men in our study might be in 10% higher risk of Ni-induced SPINA-GT and fT3 alterations, respectively. Due to the relationship established between Ni and the SPINA-GT parameter, it can be concluded that Ni has an influence on the secretory function of the thyroid gland in men. Although the further research is required, these findings suggest possible role of Ni in thyroid function disturbances.

Protocol for a double-blinded randomised controlled trial to assess the effect of faecal microbiota transplantations on thyroid reserve in patients with subclinical autoimmune hypothyroidism in the Netherlands: the IMITHOT trial

BACKGROUND

Hashimoto's thyroiditis (HT) is a common endocrine autoimmune disease affecting roughly 5% of the general population and involves life-long treatment with levothyroxine, as no curative treatment yet exists. Over the past decade, the crosstalk between gut microbiota and the host immune system has been well-recognised, identifying the gut microbiome as an important factor in host health and disease, including susceptibility to autoimmune diseases. Previous observational studies yielded a link between disruption of the gut microbiome composition and HT. This is the first study that investigates the potential of restoring a disrupted gut microbiome with faecal microbiota transplantations (FMTs) to halt disease progression and dampen autoimmunity.

METHODS AND ANALYSIS

The IMITHOT trial is a randomised, double-blinded, placebo-controlled study evaluating either autologous or allogenic FMTs in medication-naïve patients with subclinical autoimmune hypothyroidism. In total, 34 patients will be enrolled to receive either three allogenic or autologous FMTs. FMT will be made of fresh stool and directly administered into the duodenum. Patients will be evaluated at baseline before the first FMT is administered and at 6, 12 and 24 months post-intervention to assess efficacy and adverse events. The primary outcome measure will be the net incremental increase (incremental area under the curve) on thyrotropin-stimulated free thyroxine and free triiodothyronine release at 6 and 12 months compared with baseline. Results will be disseminated via peer-reviewed journals and international conferences. The recruitment of the first patient and donor occurred on 18 December 2019.

ETHICS AND DISSEMINATION

Ethics approval was obtained from the hospital Ethics Committee (Medical Ethics Committee) at Amsterdam University Medical Center. The trial's outcomes offer high-quality evidence that aids in unveiling distinct patterns within the gut microbiota potentially associated with improved thyroid function. Consequently, this may open avenues for the future clinical applications of microbial-targeted therapy in individuals at risk of developing overt HT.

TRIAL REGISTRATION NUMBER

NL7931.

Interactions between Polygenetic Variants and Lifestyle Factors in Hypothyroidism: A Hospital-Based Cohort Study

Hypothyroidism is a prevalent endocrine disorder and is associated with a variety of metabolic disturbances. This study aimed to investigate the polygenic variants associated with hypothyroidism risk and the interaction of polygenic risk scores (PRS) with dietary patterns in influencing disease risk in 56,664 participants aged >40 in a hospital-based cohort. The participants were classified as having hypothyroidism (n = 870) diagnosed by a physician and no hypothyroidism (n = 55,794). Genetic variants associated with hypothyroidism were identified using a genome-wide association study (GWAS). Genetic variants interacting with each other were selected using a generalized multifactor dimensionality reduction analysis, and the PRS generated was evaluated for interaction with lifestyle parameters. Coffee, alcohol, meat intake, and a Korean balanced diet were inversely associated with hypothyroidism risk, as were selenium, copper, and manganese intakes. White blood cell (WBC) counts and serum alkaline phosphatase and triglyceride concentrations were positively associated with hypothyroidism risk, as were osteoporosis and thyroid cancer. The GMDR analysis generated a three-single nucleotide polymorphism (SNP) model comprising dual oxidase-1 (DUOX1)_rs1648314; thyroid-stimulating hormone receptor (TSHR)_rs75664963; and major histocompatibility complex, class-II, DQ Alpha-1 (HLA-DQA1)_rs17426593. The PRS derived from the three- and seven-SNP models were associated with a 2.11- and 2.32-fold increase in hypothyroidism risk, respectively. Furthermore, the PRS from the three-SNP model showed interactions with WBC counts, wherein the positive association with hypothyroidism risk was more pronounced in participants with low WBC counts than those with high WBC counts (≥4 × 109 /L). Dietary patterns, such as the plant-based diet (PBD) and the Western-style diet (WSD), along with smoking status, exhibited interactions with the PRS, influencing hypothyroidism risk. In participants with a high PRS, those in the high-PBD, low-WSD, and smoker groups had a higher proportion of hypothyroidism than those in the low-PBD, high-WSD, and non-smoker groups. In conclusion, genetic variants related to immunity and thyroid hormone secretion were linked to hypothyroidism risk, and their PRS interacted with PBD and WSD intake and smoking status. These results contribute to a better understanding of hypothyroidism and its prevention strategies for precision medicine intervention.

Depleted uranium induces thyroid damage through activation of ER stress via the thrombospondin 1-PERK pathway

Depleted uranium (DU) can cause damage to the body, but its effects on the thyroid are unclear. The purpose of this study was to investigate the DU-induced thyroid damage and its potential mechanism in order to find new targets for detoxification after DU poisoning. A model of acute exposure to DU was constructed in rats. It was observed that DU accumulated in the thyroid, induced thyroid structure disorder and cell apoptosis, and decreased the serum T4 and FT4 levels. Gene screening showed that thrombospondin 1 (TSP-1) was a sensitive gene of DU, and the expression of TSP-1 decreased with the increase of DU exposure dose and time. TSP-1 knockout mice exposed to DU had more severe thyroid damage and lower serum FT4 and T4 levels than wild-type mice. Inhibiting the expression of TSP-1 in FRTL-5 cells aggravated DU-induced apoptosis, while exogenous TSP-1 protein alleviated the decreased viability in FRTL-5 cells caused by DU. It was suggested that DU may caused thyroid damage by down-regulating TSP-1. It was also found that DU increased the expressions of PERK, CHOP, and Caspase-3, and 4-Phenylbutyric (4-PBA) alleviated the DU-induced FRTL-5 cell viability decline and the decrease levels of rat serum FT4 and T4 caused by DU. After DU exposure, the PERK expression was further up-regulated in TSP-1 knockout mice, and the increased expression of PERK was alleviated in TSP-1 over-expressed cells, as well as the increased expression of CHOP and Caspase-3. Further verification showed that inhibition of PERK expression could reduce the DU-induced increased expression of CHOP and Caspase-3. These findings shed light on the mechanism that DU may activate ER stress via the TSP 1-PERK pathway, thereby leading to thyroid damage, and suggest that TSP-1 may be a potential therapeutic target for DU-induced thyroid damage.

Relationship between Euthyroidism and Muscle Mass and Strength: A Systematic Review

Thyroid hormones play a crucial role in skeletal muscle development, suggesting that thyroid function may influence muscle mass and muscle strength, which are both fundamental health-related indicators of several age-related consequences. However, whether there is a relationship between thyroid hormones, muscle mass, and muscle strength in individuals without thyroid dysfunctions is still unknown. Therefore, this systematic review aims to investigate whether thyroid hormones are related to muscle mass and strength parameters in euthyroid individuals. Three databases were searched (PubMed, Scopus, Web of Science) up to February 14, 2022, for peer-reviewed papers published in English. The search results were conducted independently by two different reviewers. The review included 13 studies with a total of 241,044 participants. All studies were observational: twelve studies measured thyroid stimulating hormone, ten and thirteen studies measured free triiodothyronine and free thyroxine, four studies analyzed the thyroid hormone ratio. The assessment methods for muscle mass were computed tomography, dual-energy X-ray absorptiometry and bioimpedance analysis, whereas hand dynamometer for muscle strength. Low levels within the normal range of free triiodothyronine, high levels within the normal range of free thyroxine, and lower thyroid hormone ratio may contribute to a reduced muscle function, which seems more evident in older males.

Polycystic ovary syndrome and thyroid disorder: a comprehensive narrative review of the literature

Background

Published data on the relationship between polycystic ovary syndrome (PCOS) and thyroid dysfunction are sparse and confusing.

Objective

To comprehensively review data available in the literature regarding the relationship between PCOS and the thyroid function, and its abnormalities.

Methods

Nine main areas of interest were identified and analyzed according to the available evidence: 1) Evaluation of thyroid function for PCOS diagnosis; 2) Epidemiology data on thyroid function/disorders in patients with PCOS, and vice versa; 3) Experimental data supporting the relationship between thyroid function/disorders and PCOS; 4) Effects of thyroid function/disorders on PCOS features, and vice versa; 5) Effect of thyroid alterations on the cardiometabolic risk in women with PCOS; 6) Effect of thyroid abnormalities on reproductive outcomes in women with PCOS; 7) Relationship between thyroid function/abnormalities in patients with PCOS who are undergoing fertility treatment; 8) Effect of treatments for thyroid diseases on PCOS; and 9) Effect of treatments for PCOS on thyroid function. An extensive literature search for specific keywords was performed for articles published from 1970 to March 2023 using PubMed and Web of Science. Data were reported in a narrative fashion.

Results

PCOS is a diagnosis of exclusion for which diagnosis is possible only after excluding disorders that mimic the PCOS phenotype, including thyroid dysfunctions. However, the tests and the cutoff values used for this are not specified. Many experimental and clinical data suggest a relationship between perturbations of the thyroid function and PCOS. Direct and unequivocal evidence on the effects of thyroid function/disorders on PCOS features are lacking. High thyroid-stimulating hormone levels and subclinical hypothyroidism may be associated with significant worsening of several intermediate endpoints of cardiometabolic risk in women with PCOS. Thyroid abnormalities may worsen reproductive outcomes, especially in patients undergoing fertility treatment. To date, there are no data demonstrating the efficacy of thyroid medications on fertility and cardiometabolic risk in women with PCOS. Lifestyle modification changes, metformin, and vitamin D seem to improve thyroid function in the general population.

Conclusion

PCOS and thyroid disorders are closely related, and their coexistence may identify patients with a higher reproductive and metabolic risk. Regular screening for thyroid function and thyroid-specific autoantibodies in women with PCOS, particularly before and during pregnancy, is highly recommended.

Association between thyroid stimulating hormone levels and papillary thyroid cancer risk: A meta-analysis

High thyroid stimulating hormone (TSH) levels may stimulate papillary thyroid cancer (PTC) cell proliferation; however, the relationship between TSH levels and PTC risk remains controversial. We aim to ascertain the association through a meta-analysis. Literature searches were conducted in PubMed, Embase, and Web of Science databases. After literature screening, the methodological quality was assessed using the Newcastle-Ottawa Scale and Agency for Healthcare Research and Quality methods. Cochran's Q and I 2 tests were used to evaluate heterogeneity in the meta-analysis. Egger's test was applied to assess publication bias. A total of 12 eligible studies were included in this meta-analysis; all were of moderate and high methodological quality. The pooled results suggested that increased TSH levels were significantly associated with PTC risk; however, the included studies were significantly heterogeneous. Stratification analysis indicated that the heterogeneity might be from the area or type of control. Although significant publication bias existed among the studies, the trim-and-fill method and sensitivity analysis revealed that the combined results were stable and robust. TSH levels are significantly associated with the PTC risk; however, more high-quality studies in large sample sizes are recommended to verify the extrapolation of these findings.

Exposure to mixed chemicals elevated triiodothyronine (T3) and follicle-stimulating hormone (FSH) levels: epidemiology and in silico toxicogenomic involvement

There is a dearth of evidence on the effects of a mixture of numerous different types of chemicals on hormone functions. We hypothesized that exposure to mixed chemicals may alter hormone levels. Thus, this study was to identify an association between the mixed chemicals (25 chemicals) and hormone levels (thyroxine (T4) and triiodothyronine (T3), thyroid-stimulating hormone (TSH), and follicle-stimulating hormone (FSH)) among 5687 Korean adults using four different statistical approaches. Furthermore, we elucidate the effects of the key chemicals on thyroid disease and infertility based on the findings from epidemiology data. The positive associations between mixed chemicals and T3 and between mixed chemicals and FSH were observed across different methods after adjusting for all possible confounders. In the weighted quantile sum regression models, there were positive associations between mixed chemicals and T3 (β = 4.43, 95%CI: 2.81-5.88) and ln-transformed FSH (lnFSH) (β = 0.15, 95%CI: 0.10-0.20). In the quantile g-computation models, positive associations were found between mixed chemicals and T3 (β=2.15, 95%CI: 0.17-4.14) and lnFSH (β=0.15, 95%CI: 0.07-0.22). In the Bayesian kernel machine regression models, culminative effects of mixed chemicals showed positive associations with T3 and lnFSH; mercury (group posterior inclusion probabilities (PIPs) = 0.557 and conditional PPI = 0.556) and lead (group PIP group = 0.815 and conditional PPI = 0.951) were the most important chemicals for T3 and FSH, respectively. The results obtained were partially robust when subjected to in silico toxicogenomic data. We identified several molecular mechanisms that were implicated in Hg-induced thyroid disease, including the selenium micronutrient network, oxidative stress response, IL-17 signaling pathway, poorly differentiated thyroid carcinoma, and primary hyperthyroidism. The molecular processes implicated in Pb-induced infertility were "response to nutrient levels," "gonad development," "male infertility," "female infertility," and "intrinsic pathway for apoptosis," with a particular focus on FSH. The present study investigated the threshold levels of the studied chemicals and their potential impact on the disruption of T3 and FSH hormones. Future research is warranted to determine the effects of mixed chemicals on various hormones because there have been few studies on the disruption of hormones caused by such mixed chemicals.

Screening eco-friendliness tire antioxidants alternatives: functional 2,2,4-trimethyl-1,2-dihydroquinoline derivatives design and toxicity evaluation

Antioxidants which are indispensable functional additives used in rubber tires, are released into aquatic habitats from tire wear particles (TWP), collected in water bodies, and threaten the aquatic ecosystem. This study aimed to design eco-friendly derivatives of 2,2,4-trimethyl-1,2-dihydroquinoline (TMQ) with increased antioxidant activity to use as tire antioxidants. Initially, seventy highly efficient derivatives of TMQ were designed by hydroxylation modifications at multiple sites. The antioxidant activity of hydroxyl derivatives was characterized based on DFT method and compared with TMQ. Twenty derivatives showing a significant (greater than 9%) increase in antioxidant activity compared to TMQ were selected for the next stage. The toxicity risk of these twenty TMQ derivatives was assessed using various toxicokinetic methods. Finally, six TMQ derivatives with significantly lower toxicity risk compared to that of TMQ were evaluated for potential developmental toxicity. They were characterized using molecular docking and molecular dynamics techniques to assess the developmental toxicity risk in silver salmon by absorption of their ROO·, HO·, O2·- and O3 derivatives. TMQ-6 and TMQ-48 showed the lowest toxicity among all TMQ derivatives by a rather large margin. The study throws light on the path of future endeavors to develop highly efficient and greener tire antioxidants.

Associations of perchlorate, nitrate, and thiocyanate with metabolic syndrome and its components among US adults: A cross-sectional study from NHANES

Perchlorate, nitrate and thiocyanate are common endocrine disruptors. Herein, this study was undertaken to evaluate the associations between perchlorate, nitrate, and thiocyanate exposures (alone or in combination) and risk of metabolic syndrome (MetS) among adults, which has not been explored so far. Analytical data were extracted from different datasets in the National Health and Nutrition Examination Survey (NHANES) database. Multivariate logistic regression models were constructed to investigate the associations between perchlorate, nitrate, and thiocyanate exposures, and the prevalence of MetS. Subsequently, odds ratios (OR) and their corresponding 95 % confidence intervals (CIs) were adopted to represent the magnitude of the effect size. We performed a series of subgroup analyses and sensitivity analyses as well. Moreover, three commonly used mixture modeling strategies [Weighted quantile sum (WQS) regression, quantile-based g-computation (Qgcomp), and Bayesian kernel machine regression (BKMR)] were utilized to evaluate the joint mixture effect on MetS. This study included 12,007 participants in the subsequent analyses. After adjustment for confounding factors, higher levels of perchlorate, and thiocyanate concentrations were significantly associated with the risk of MetS (OR = 1.15, 95%CI:1.00, 1.32; OR = 1.21, 95%CI:1.04, 1.41, respectively). Analyses of WQS and Qgcomp showed that a quartile increase in chemical mixture was correlated with the occurrence of MetS with ORs of 1.07 (95%CI: 0.99, 1.16) and 1.07 (95%CI: 1.00, 1.14), respectively. This positive association was mainly driven by perchlorate and thiocyanate. Analysis of BKMR revealed that perchlorate, nitrate, and thiocyanate mixture was positively associated with the risk of MetS while perchlorate, and thiocyanate were major predictors in the mixture. In summary, our study reveals positive relationships between perchlorate, thiocyanate and MetS. Co-exposure to perchlorate, nitrate and thiocyanate is positively associated with the risk of MetS, with perchlorate and thiocyanate contributing the most to the overall mixture effect.

Estimation of bloodstain deposition time within a 24-h day-night cycle with rhythmic mRNA based on a machine learning algorithm

Estimating the time that bloodstains are left at a crime scene can provide invaluable evidence for law enforcement investigations, including determining the time of the crime, linking the perpetrator to the crime scene, narrowing the pool of possible suspects, and verifying witness statements. There have been some attempts to estimate the time since deposition of bloodstains, i.e., how much time has passed since the bloodstain was left at a crime scene. However, most studies focus on the time interval of days. As far as we know, previous study have been conducted to estimate the deposition time of blood within a 24-h day-night cycle. To date, there is a lack of studies on whether rhythmic mRNA of blood is suitable for bloodstain samples. In this study, we estimated the bloodstain deposition time within a 24-h day-night cycle based on the expression of messenger RNAs (mRNAs) by real-time quantitative polymerase chain reaction. Bloodstain samples were prepared from eight individuals at eight time points under real and uncontrolled conditions. Four mRNAs expressed rhythmically and were used to construct a regression model using the k-nearest neighbor (KNN) algorithm, resulting in a mean absolute error of 3.92 h. Overall, using the rhythmic mRNAs, a machine learning model was developed which has allowed us to predict the deposition time of bloodstains within the 24-h day-night cycle in East Asian populations. This study demonstrates that mRNA biomarkers can be used to estimate the bloodstain deposition time within a 24-h period. Furthermore, rhythmic mRNA biomarkers provide a potential method and perspective for estimating the deposition time of forensic traces in forensic investigation. Case samples in forensic analysis are usually limited or degraded, so the stability and sensitivity of rhythmic biomarkers need to be further investigated.

Age-based factors modulating the required thyroxine dose to achieve thyrotropin suppression in intermediate-and high-risk papillary thyroid cancer

Background

Guidelines widely recommend thyrotropin suppression to reduce the risk of recurrence in intermediate- and high-risk papillary thyroid cancer (PTC) after total thyroidectomy. However, an insufficient or excessive dosage may result in a number of symptoms/complications especially in older patients.

Patients and methods

We constructed a retrospective cohort including 551 PTC patient encounters. Using propensity score matching and logistic regression models, we determined the independent risk factors affecting levothyroxine therapy at different ages. Our outcomes included: expected TSH level and an unexpected TSH level, which was based on the initial thyroid-stimulating hormone (TSH) goal< 0.1 mIU/L with usual dosage of L-T4 (1.6 μg/kg/day).

Results

From our analysis, more than 70% of patients undergoing total thyroidectomy did not achieve the expected TSH level using an empirical medication regimen, and the effect of the drug was affected by age (odds ratio [OR], 1.063; 95% CI, 1.032-1.094), preoperative TSH level (OR, 0.554; 95% CI, 0.436-0.704) and preoperative fT3 level (OR, 0.820; 95% CI, 0.727-0.925). In patients with age < 55 years old, preoperative TSH level (OR, 0.588; 95% CI, 0.459-0.753), and preoperative fT3 level (OR, 0.859; 95% CI, 0.746-0.990) were two independent protective factors, while, in patients with age ≥ 55 years old, only preoperative TSH level (OR, 0.490; 95% CI, 0.278-0.861) was the independent protective factors to achieve expected TSH level.

Conclusion

Our retrospective analysis suggested the following significant risk factors of getting TSH suppression in PTC patients: age (≥55 years), lower preoperative TSH and fT3 levels.