Up-regulation of FTO gene expression was associated with increase in skeletal muscle mass in overweight male adolescents

The effects of macro-algae supplementation on serum lipid, glycaemic control and anthropometric indices: A systematic review and meta-analysis of clinical trials

INTRODUCTION

Macro-algae products have been shown to ameliorate the metabolic disorders state. Thus, highlighting their function as supplementary therapeutic agents can be a novel strategy for clinical therapies. This systematic review and meta-analysis of clinical trials aimed to summarize the effect of macro-algae consumption on serum lipid profile, glycaemic control and anthropometric factors.

METHODS

In this systematic review and meta-analysis, a comprehensive search was performed for relevant studies published up to May 2023. The Cochran's Q test and I-square (I2 ) tests were used to evaluate heterogeneity across the included studies. The meta-analysis was conducted using random-effects model (DerSimonian and Laird), and weighted mean difference (WMD) was considered as the pooled effect size.

RESULTS

Out of 8602 papers in the initial screening, eight clinical trials with a total of 438 participants were included into this meta-analysis. The results indicated that macro-algae supplementation significantly decreased serum levels of total cholesterol (TC) (WMD = -6.7 mg/dL; 95% CI: -12.59, -0.80; item = 0.026) and low-density lipoprotein cholesterol (LDL-c) (WMD = -8.25 mg/dL; 95% CI: -15.38, -1.12; p-value = .023). There was an increase in level of high-density lipoprotein cholesterol (HDL-c) (WMD = 0.48 mg/dL; 95% CI: -2.05, 3.01; p-value = .71) which was not statistically significant. Macro-algae supplementation reduced body mass index (BMI) (WMD = -0.28 kg/m2 ; 95% CI: -0.96, 0.41; p-value = .426), weight (WMD = -0.39 kg; 95% CI: -3.6, 2.83; p-value = .81), waist circumference (WC) (WMD = -0.52 cm; 95% CI: -2.71, 1.66; p-value = .64), fasting blood sugar (FBS) (WMD = -1.95 mg/dL; 95% CI: -5.19, 1.28; p-value = .24) and HbA1c (WMD = -0.02%; 95% CI: -0.14, 0.09; p-value = .66) in intervention group.

CONCLUSIONS

This meta-analysis indicated that macro-algae supplementation significantly decreased TC and LDL-c level. It can also increase HDL-c level and reduce anthropometric indices and glycaemic control factors.

Identification of gene polymorphisms associated with fat mass by genome-wide association study in Chinese people

Introduction

This study aimed to investigate the relationship of gene polymorphisms and fat mass (FM) in Chinese population.

Methods

Healthy males, premenopausal and postmenopausal women were recruited. Single Nucleotide Polymorphisms (SNPs) and FM were measured.

Results

The rs141206415 in the RASAL1 gene and rs144493374 in the PALLD gene were associated with trunk FM, and the rs4807023 in the PTPRS gene was associated with leg FM using Spearman correlation analysis.

Conclusions

The results suggest that the RASAL1 gene and the PALLD gene might contribute to variability of trunk FM in healthy Chinese Han people. The PTPRS gene is potentially correlated with leg FM. Our findings provide a clue in fat metabolism.

The effect of FTO rs9939609 polymorphism on the association between colorectal cancer and dietary fiber

Background

Gene polymorphisms may explain the controversy on the association between colorectal cancer (CRC) and dietary fibers. The purpose of this study was to investigate the effect of fat mass and obesity-associated (FTO) rs9939609 polymorphism on the association between colorectal cancer and dietary fiber.

Methods

This case-control study was conducted on 160 CRC cases and 320 healthy controls in Tehran, Iran. The participants' food intake was assessed using a semi-quantitative food frequency questionnaire (FFQ). The frequency of rs9939609 FTO polymorphism in the case and control groups was determined using the tetra-primer amplification refractory mutation (tetra-ARMS) method.

Results

In the participants with the TT genotype of the FTO rs9939609, the cases had higher BMI and lower intake of dietary fiber compared to the controls (P = 0.01). Among A allele carriers of FTO rs9939609 polymorphism, the cases had higher BMI (P = 0.04) and lower intake of total fiber (P = 0.02) and soluble fiber (P = 0.02). An inverse association was found between CRC and dietary fiber intake among those with the AA/AT FTO rs9939609 genotype after adjusting for age, sex, smoking, alcohol consumption, physical activity, BMI, and calorie intake (OR = 0.9, CI 95%:0.84-0.92, P < 0.05).

Conclusion

This study found a link between higher dietary fiber consumption and a lower risk of CRC in A-allele carriers of FTO rs9939609 polymorphism. Future studies are needed to identify the underlying mechanisms of the association between CRC and dietary fibers in people with different FTO genotypes.

Sevoflurane Inhibits lncRNA HOTAIR-Modulated Stability of HK2 mRNA in a m6A-Dependent Manner to Dampen Aerobic Glycolysis and Proliferation in Lung Cancer

Previous studies have shown that sevoflurane has an inhibitory effect on tumor cells. So far, the effect of sevoflurane on hepatocellular carcinoma needs to be confirmed by more studies. HOX transcript antisense intergenic RNA (HOTAIR), a long noncoding RNA (lncRNA), has been shown to enhance cancer cell proliferation and medication resistance. The inherent importance and biological function of HOTAIR in the course of lung cancer (LC) is, however, poorly unclear. HOTAIR was shown to be highly elevated in LC cells in this investigation. Impairment of function trials with sevoflurane indicated that it has anticancer effects on LC cell growth, apoptosis, and aerobic glycolysis. In a mechanistic manner, HOTAIR was related to HK2 mRNA and promoted expression and constancy. Additional research revealed that HOTAIR coupled with hexokinase 2 (HK2) mRNA and favorably controlled its stabilization in a traditional-component way. By HK2, the LC enhancement role was mediated. In summary, our data show that HOTAIR promotes the synthesis and proliferation of LC glycogen by increasing the transcription of HK2, and HOTAIR is likely to be a potential treatment for LC patients.

C-myc/TSPEAR-AS2 Axis Facilitates Breast Cancer Growth and Metastasis in a GLUT1-Dependent Glycolysis Manner

A large number of facts have shown that epigenetic modification and metabolic reprogramming represented by noncoding RNA play an important role in the invasion and metastasis of breast cancer, but the mechanism is not clear. The purpose of our study is to find a new biomarker of breast cancer and to provide a new perspective for regulating glucose metabolism and aerobic glycolysis of BC. In this paper, by downregulating C-myc protein, our team found that the expression of long-chain noncoding RNATSPAR-AS2 was significantly downregulated. However, the expression of long-chain noncoding RNASPAR-AS2 in BC is relatively high, and the prognosis is poor. TSPEAR-AS2 can promote the malignant phenotype of BC cells, including proliferation, apoptosis, invasion and metastasis, and glycolysis. At the same time, TSPEAR-AS2 can also upregulate the expression of GLUT1, an important regulator of glycolysis, thus promoting the metabolic reprogramming of BC. Molecular mechanism experiments show that TSPEAR-AS2 may promote the expression of GLUT1 by participating in IGF2BP2 modified by the GLUT1 gene. Our results suggest that the C-myc/TSPEAR-AS2/GLUT1 axis promotes the invasion and metastasis of BC by inducing glucose metabolism reprogramming. However, more phenotypic and molecular mechanism results need to be further verified.

Intake of food groups and cervical cancer in women at risk for cervical cancer: A nested case-control study

Background

The risk of cervical cancer was reported to be influenced by dietary components. This study aimed to illustrate the association between cervical cancer with the intake of food groups in women with a history of cervical neoplasia.

Methods

This nested case-control study was conducted in 558 people with a history of cervical intraepithelial neoplasia (CIN), including 279 women with cervical cancers and 279 controls with low-grade squamous intraepithelial lesions (LSIL). A validated food frequency questionnaire (FFQ) was used to assess the intake of food groups.

Results

The intake of fruits and vegetables in the case group was significantly lower than the control group (P=0.001). Low intake of dairy products, vegetables, and fruits was associated with cervical cancer risk (OR=4.67; 95% CI 1.2-9.49, P=0.001; OR=9.75, 95% CI 1.36-19. 51, P=0.001; and OR=4.82, 95% CI 1.09-7.25, P=0.001, respectively). After adjusting for age, family history, age at first menstruation, number of children, history of vaginal infection, and age at first sexual intercourse, the results were still significant. Additional adjustments to BMI did not change the results.

Conclusion

The results indicate that the risk of cervical cancer can be affected by the intake of certain food groups. Further longitudinal studies are needed to confirm these findings and determine the underlying mechanism of the influence of dietary components on cervical cancer risk.

Association between different types of dietary carbohydrate and breast cancer

BACKGROUND

Among modifiable lifestyle factors, unhealthy dietary intake is associated with higher risks of breast cancer (BC). This paper aimed to investigate the association of different types of dietary carbohydrate with BC risk among women 20-75 years old.

DESIGN

This case-control study was carried out on 180 women with BC and 360 healthy individuals as the control group. Basic information including anthropometric measurements, medical history, physical activity, alcohol consumption, reproductive histories, smoking, and education level were collected. The amount of intake of carbohydrate, simple sugar, sucrose, maltose, and fructose were assessed using food frequency questionnaire (FFQ).

RESULTS

The amounts of intake of total carbohydrate [odds ratio (OR) = 1.76; 95% confidence interval (CI) (1.24-2.14); P = 0.01], simple sugar (OR = 1.95, 95% CI (1.42-3.39); P = 0.01), sucrose (OR = 1.97, 95% CI (1.18-3.12); P = 0.02), maltose (OR = 4.07, 95% CI (1.68-8.14); P = 0.03), and fructose (OR = 1.104, 95% CI (1.06-1.36); P = 0.01) were positively associated with BC after adjustments for age, body mass index (BMI), smoking, using alcohol, physical activity, and dietary intake of calorie, protein, and fat. No significant association was found between the intake of glucose, galactose, and lactose with BC.

CONCLUSIONS

The results of this study identified that some types of dietary carbohydrates may play a role in the development of BC. Different monosaccharides and disaccharides may have different effects on the risk of breast cancer. Further longitudinal studies are warranted to identify the effects of carbohydrates on BC and to explore the underlying mechanisms.

The correlation between serum inflammatory, antioxidant, glucose handling biomarkers, and Dietary Antioxidant Index (DAI) and the role of DAI in obesity/overweight causation: population-based case-control study

BACKGROUND

Obesity is a multifactorial disease, and about 40% of world adults are overweight, and about 20% are obese. Diet is one of the most important factors in the causality of obesity. The interactions between the diet and gut microbiota or chronic inflammation pathways highlight the importance of its various aspects in the incidence and prevalence of obesity. At the same time, diet is a combination of several antioxidants that are needed together for the body's antioxidant system. The Dietary Antioxidant Index (DAI) is a valid nutritional tool, and its correlation has been studied concerning total antioxidant capacity and malondialdehyde. The study aimed to examine the relationship between the DAI and the odds of obesity. We hypothesized that a higher DAI score indicating a predominantly antioxidant diet has a protective effect against odds of obesity.

METHODS

In this population-based case-control study, 812 participants with a higher body mass index (BMI) than 25 were selected as the case group. Also, 793 participants with BMI in the range of 17.9-24.9 were selected as the control group. A valid and reliable 124-item food frequency questionnaire (FFQ) was used to assess dietary intake. Based on FFQ data, we summed up the standardized intake of the major dietary antioxidants, including vitamin A, E, C, selenium, zinc, and manganese, to calculate DAI.

RESULTS

In a multivariable adjusting model, there was a significant association between DAI (as a continuous variable) and BMI (odds ratio (OR) = 0.95; 95% CI: 0.92-0.99; P value = 0.02). Also, there was a significant association between DAI (as a categorized variable) and body surface area with multivariable adjusting model (OR = 0.79; 95% CI: 0.64-0.98; P value = 0.04).

CONCLUSION

In conclusion, the DAI can accurately predict some serum antioxidant and anti-inflammatory levels along with glucose handling markers.

The Association of Fat-Mass-and Obesity-Associated Gene Polymorphism (rs9939609) With Colorectal Cancer: A Case-Control Study

Background and Aim

The association between the rs9939609 polymorphism of fat mass and obesity-associated gene (FTO) and risk of colorectal cancer is controversial. This study aims to evaluate the relationship between FTO rs9939609 polymorphism and colorectal cancer (CRC) in Iranian people.

Methods

A case-control study was conducted on 125 patients with CRC and 250 healthy subjects in Tehran, Iran. Demographic data and blood samples were collected from all participants. Genotyping of rs9939609 polymorphism was performed by the tetra-primer amplification refractory mutation system-polymerase chain reaction (T-ARMS-PCR) method.

Results

The occurrence of AA genotype of FTO rs9939609 polymorphism in the colorectal cancer patients was significantly higher compared to that of healthy subjects (16.4 vs. 2.9%, respectively, P=0.02). The association between the frequency of risk allele of the FTO polymorphism and CRC (B=1.67, P=0.042) remained significant after adjustment for age. Further adjustment for gender (model 2) and marital status (model 3) did not change this result (B=1.67, P= 0.042 and B=1.67, P=0.043, respectively). The results remained significant after additional adjustment for ethnicity (B=1.57, P= 0.047).

Conclusion

We found a positive association between the A allele of the rs9939609 polymorphism and CRC. Future studies are required to identify the underlying mechanisms.

The effects of saffron petals and damask rose petals on biochemical and inflammatory measurements

OBJECTIVES

Diabetes is a chronic disease caused by high blood sugar greatly affected by diet. The chemical medicines applied to treat diabetes usually have side effects. This study aimed to investigate the effect of saffron petals, damask rose petals, and saffron-damask rose petal herbal teas on weight loss, fasting blood sugar, lipid profile, and the inflammatory factors of diabetic rats.

METHODS

In this study, 40 male Sprague Dawley rats with an average age of four weeks received a high-calorie, high-fat, high-sugar diet for nine weeks. The rats were then randomly assigned to five groups, including normal, control, saffron petal, damask rose petal, and saffron plus damask rose petal groups. For nine weeks, 3 mL of the herbal tea was administered to the intervention groups daily through oral gavage. The levels of FBS, lipid profile, Insulin-like growth factor 1 (IGF-1), the high-sensitivity C-reactive protein (hs-CRP), hemoglobin A1c (HbA1C), and glucose tolerance test (GTT) were measured following the intervention.

RESULTS

Saffron petals reduced weight gain, Triglyceride (TG), and HbA1c and increased hs-CRP and IGF-1 (all p < 0.05). The damask rose petal reduced weight gain, FBS, hs-CRP, and HbA1c and increased the IGF-1 (all p < 0.05). Saffron plus damask-rose petals reduced the weight gain, TG, hs-CRP and HbA1c, and increase IGF-1 factor (all p < 0.05) compared to the control group. No significant effect was found on visceral fat, LDL-C, and HDL-C. Compared with the normal group, saffron petals and damask rose petals increased the FBS, HDL, and LDL levels. Damask rose and the combination of saffron petals and damask rose decreased IGF-1 compared with the normal group (all p < 0.05).

CONCLUSIONS

Saffron and damask rose petals could have beneficial effects on improving the status of biochemical markers. The simultaneous use of saffron and damask rose may counteract the adverse effects of saffron on inflammatory indices.

The association between fat mass and obesity-associated (FTO) genotype and serum vitamin D level in breast cancer patients

The preventive effect of vitamin D against breast cancer can be influenced by gene polymorphisms. This study aimed to investigate the association between serum level of 25(OH) vitamin D and FTO genotype in breast cancer patients. A cross‐sectional study was carried out on 180 newly diagnosed patients with breast cancer in Tehran, Iran. The blood samples were collected from the participants in order to assess the FTO gene rs9939609 polymorphism by the tetra‐primer amplification refractory mutation system (Tetra‐ARMS) PCR method. The serum level of 25(OH) vitamin D was measured using the direct competitive enzyme‐linked immunosorbent assay (ELISA) method. The association between vitamin D and the FTO genotype in patients with breast cancer was assessed after adjustment for cofounders. The frequency of TT, AT and AA genotypes in the breast cancer patients were 43% (n = 77), 49% (n = 89) and 8% (n = 14), respectively. All patients with higher than 40 ng/dl of serum 25(OH) vitamin D had one or two copies of FTO rs9939609 risk allele (p = 0.019). No linear association was found between the number of FTO risk allele and the level of serum vitamin D. All patients with high serum level of 25(OH) vitamin D had one or two copies of FTO rs9939609 risk allele. FTO gene polymorphisms may counteract the beneficial effects of vitamin D in breast cancer prevention. Further studies can help to better understand the genetic factors predisposing to breast cancer and their effect on the association between vitamin D and breast cancer.

Long noncoding RNA just proximal to X-inactive specific transcript facilitates aerobic glycolysis and temozolomide chemoresistance by promoting stability of PDK1 mRNA in an m6A-dependent manner in glioblastoma multiforme cells

Improving the chemotherapy resistance of temozolomide (TMZ) is of great significance in the treatment of glioblastoma multiforme (GBM). Long non-coding RNA just proximal to the X-inactive specific transcript (JPX) has been proven to be involved in cancer progression. However, the intrinsic significance and molecular mechanism by which JPX orchestrates GBM progression and TMZ chemotherapy resistance remain poorly understood. Here, JPX was found to be significantly elevated in GBM tissues and cell lines, and patients with high expressions of JPX showed significantly worse prognoses. Functional experiments revealed its carcinogenic roles in GBM cell proliferation, TMZ chemoresistance, anti-apoptosis, DNA damage repair, and aerobic glycolysis. Mechanistically, JPX formed a complex with phosphoinositide dependent kinase-1 (PDK1) messenger RNA (mRNA) and promoted its stability and expression. Furthermore, an RNA immunoprecipitation (RIP) experiment showed that JPX interacted with N6-methyladenosine (m6A) demethylase FTO alpha-ketoglutarate dependent dioxygenase (FTO) and enhanced FTO-mediated PDK1 mRNA demethylation. JPX exerted its GBM-promotion effects through the FTO/PDK1 axis. Taken together, these findings reveal the key role of JPX in promoting GBM aerobic glycolysis and TMZ chemoresistance in an m6A-dependent manner. Thus, it comprises a promising novel therapeutic target for GBM chemotherapy.

The association between sarcopenia susceptibility and polymorphisms of FTO, ACVR2B, and IRS1 in Tibetans

Background

Hypoxia within the plateau has a negative effect on skeletal muscle and may play a role in the development of sarcopenia in humans. Tibetans having lived in the Qinghai‐Tibet Plateau for thousands of years, are a high‐risk group for sarcopenia; however, they have a distinctive suite of genetic traits that enable them to tolerate environmental hypoxia and are genetically significantly different from Han Chinese and other lowland populations. Sarcopenia has been consistently found to be associated with single‐nucleotide polymorphisms, but few studies have investigated the role of single‐nucleotide polymorphisms in a range of muscle phenotypes and sarcopenia in Tibetan peoples.

Methods

Our study aimed to investigate the skeletal muscle mass and fat mass of 160 Tibetans (80 men and 80 women) from Lhasa (altitude of 3600 meters) and analyze the association between the polymorphisms of fat mass and obesity protein (FTO) rs9939609, FTO rs9936385, activin type IIB receptor (ACVR2B) rs2276541, insulin receptor substrate 1 (IRS1) 2943656 and sarcopenia.

Result

FTO rs9939609 and rs9936385 polymorphisms were associated with lower limb skeletal muscle mass and sarcopenia for Tibetan women, and TT homozygotes had a higher risk for sarcopenia. But ACVR2B rs2276541 and IRS1 2943656 polymorphisms were unassociated with sarcopenia in Tibetan.

Conclusion

In Tibetans, FTO rs9939609 and rs9936385 polymorphisms were associated with sarcopenia, and ACVR2B rs2276541 and IRS1 2943656 polymorphisms were unassociated with sarcopenia.

Structural characteristics of small-molecule inhibitors targeting FTO demethylase

Studies have shown that the FTO gene is closely related to obesity and weight gain in humans. FTO is an N⁶-methyladenosine demethylase and is linked to an increased risk of obesity and a variety of diseases, such as acute myeloid leukemia, type 2 diabetes, breast cancer, glioblastoma and cervical squamous cell carcinoma. In light of the significant role of FTO, the development of small-molecule inhibitors targeting the FTO protein provides not only a powerful tool for grasping the active site of FTO but also a theoretical basis for the design and synthesis of drugs targeting the FTO protein. This review focuses on the structural characteristics of FTO inhibitors and discusses the occurrence of obesity and cancer caused by FTO gene overexpression.

Relationship between the skeletal muscle mass index and physical activity of Japanese children: A cross-sectional, observational study

Regular physical activity is an important component of physical health of children and has been associated with increasing skeletal muscle mass and muscle strength. Children with low levels of physical activity may experience health problems, such as loss of muscle mass, later in life. Thus, it may be valuable to identify declining physical function in children who do not perform the recommended amount of physical activity. Therefore, we aimed to evaluate the relationship between the amount of physical activity performed for ≥60 min per day for ≥5 days per week and the skeletal muscle mass index and physical function in young children. In total, 340 typically developing children aged 6–12 years (175 girls; average age, 9.5±1.9 years) were included in this cross-sectional study. We evaluated the proportion of children performing the recommended minimum of 60 min of daily moderate-to-vigorous physical activity at least 5 days per week. The skeletal muscle mass and Gait Deviation Index scores, gait speed, grip strength, Five Times Sit-to-Stand test results, Timed Up-and-Go test results, one-leg standing time, and gait efficiency were evaluated. Multiple logistic regression analyses were performed to assess the association of moderate-to-vigorous physical activity with the skeletal muscle mass index, percent body fat, and physical function, after controlling for confounding factors (age and sex). A logistic regression analysis revealed that the skeletal muscle mass index was independently associated with moderate-to-vigorous physical activity (odds ratio, 2.34; 95% confidence interval, 1.17–4.71; P = 0.017). Performance of moderate-to-vigorous physical activity for ≥5 days per week for ≥60 min per day was associated with the skeletal muscle mass index score of Japanese children. Our findings highlighted the importance of performing moderate-to-vigorous physical activity for the development of skeletal muscle mass in children.

Associations between FTO rs9939609 polymorphism, serum vitamin D, mental health, and eating behaviors in overweight adults

Background: Despite the significant role of the Fat Mass and Obesity-Associated (FTO) gene in obesity, the underlying mechanisms are not fully elucidated. Besides, vitamin D deficiency and obesity are mostly seen together, and it can be hypothesized that this nutrient may have an impact in the role of FTO genotype in adiposity.Objective: Thus, this study aimed to investigate the association of FTO rs9939609 gene polymorphism with eating behaviors, eating disorders, and general mental health in overweight adults, considering their vitamin D intake as a mediate confounding factor.Methods: This cross-sectional study was carried out on 197 overweight adults in Shiraz, Iran. Genotyping was performed through amplification refractory mutation system polymerase chain reaction (ARMS PCR). Mental health, vitamin D intake, eating behaviors and disorders were assessed by the validated questionnaires.Results: The risk allele of the FTO rs9939609 polymorphism (A) was significantly associated with a higher risk of eating behavior and mental health disorders (all P < 0.05). After considering vitamin D intake, the AA genotype carriers had significantly higher risks for poorer eating behavior (P = 0.002), mental health (P = 0.007), and general mental health (P = 0.039) compared with the TT carriers if they had insufficient vitamin D intake.Conclusion: In conclusion, these results indicated that the A-allele of the FTO rs9939609 polymorphism may be associated with poorer eating behaviors, mental health, and higher risk of eating disorders. It was also identified that the effect of FTO rs9939609 A risk allele on eating behavior and mental health may be limited to people with insufficient vitamin D intake.

Does vitamin D affect the association between FTO rs9939609 polymorphism and depression?

Background & objectives: Depression is a highly prevalent and multifactorial psychological disorder. Fat Mass and Obesity-Associated (FTO) gene and the serum vitamin D level are proposed to be involved in pathophysiology of depression. This study aimed to investigate the interactions between one FTO gene single nucleotide polymorphism, depression, and serum vitamin D level in overweight adults.Methods: One hundred and ninety-seven overweight adults were recruited in this cross-sectional study. FTO genotyping was performed by amplification refractory mutation system polymerase chain reaction (ARMS-PCR). Depression severity was assessed using Beck's depression inventory (BDI-II). Serum vitamin D levels were measured using a direct competitive enzyme-linked immunosorbent assay (ELISA) method.Results: A-allele carriers had higher Beck's depression score (P = 0.03). Multivariate regression models showed a positive association between the A-allele of FTO rs9939609 polymorphism and depression. Serum vitamin D level had no effect on the association between FTO genotype and depression.Conclusion: A-allele of FTO rs9939609 polymorphism might be associated with depression independent of serum vitamin D level. Further longitudinal studies are needed to confirm these results.

The eccentric mechanotransduction, neuro-muscular transmission, and structural reversibility of muscle fatty infiltration. An experimental advanced disuse muscle-wasting model of rabbit supraspinatus

INTRODUCTION

Full-thickness rotator cuff tear is present in almost 50% of patients over age 65 years, and its degree is known to be a good predictor of the severity of muscle-wasting (MW) sarcopaenia, also known as fatty degeneration (FD). A FD CT grade > 2° is recognized as a borderline of its reversibility. A disuse model of supraspinatus FD (grade 2) in rabbits provides clinically relevant data. Therefore, the present study evaluates the correlation between eccentric mechanotransduction, neuromuscular transmission (NT), and reversibility of muscle fatty infiltration (MFI) in rabbit supraspinatus FD > 2°.

MATERIAL AND METHODS

The supraspinatus tendon was detached from the greater tubercle, infraspinatus, and subscapularis in 16 rabbits. The tendon was reinserted after 12 weeks, and the animals were euthanized 24 weeks after reconstruction. MFI was measured in the middle part of the supraspinatus. Single-fibre EMG (SFEMG) examination of the supraspinatus NT was performed on 4 animals.

RESULTS

The power of analysis was 99%. Significant differences in MFI volume were found between the operated (4.6 ±1.1%) and the opposite control sides (2.91 ±0.61%) (p < 0.001). SFEMG revealed no significant differences between the disuse and the control supraspinatus muscles (p > 0.05); however, 6.5% of the examined muscle fibres exhibited NT disorders combined with blockade of conduction in 2.5% of muscle fibres.

CONCLUSIONS

Critical MFI in a disuse model of rabbit supraspinatus FD, CT grade > 2°, is substantially reversible by eccentric training despite subclinical impairment of neuromuscular transmission. In addition, 0.63% reversal of MFI is correlated with 1% hypertrophy of type I and II muscle fibre diameter.

Association Between Parental Socioeconomic Status and Skeletal Muscle Mass in Chinese College Students: Fitness Improvement Tactics in Youths (FITYou) Project

Purpose

The purpose of this study was to determine the association between parental socioeconomic status (SES) and skeletal muscle mass in Chinese college students.

Methods

A cross-sectional study including 2204 college freshmen was conducted in Shenyang, China. Data regarding body composition, health examinations, and a self-reported questionnaire were available from all the participants. Skeletal muscle mass assessment was completed by a bioelectrical impedance analyzer. Information on parental SES (educational levels, annual income, and occupational status) was collected via questionnaires. Covariance analysis was used to adjust for the confounding effects of sex, age, ethnicity, smoking status, alcohol use, and sleep duration.

Results

Multivariate analysis showed that college freshmen with higher parental SES levels generally had higher skeletal muscle mass after adjustment for confounding factors (mean [95% confidence interval]: low, 42.4 [42.0, 42.8]; middle, 42.9 [42.6, 43.3]; high, 43.7 [43.4, 44.1], p for trend < 0.001). Similar results were observed for paternal and maternal SES (p for trend < 0.001, respectively), whereas association between paternal SES and youth muscle mass became non-significant after adjusting for maternal SES (p for trend = 0.077). Results also showed positive linear trends for skeletal muscle mass and paternal or maternal educational levels and annual income (p for trend < 0.001, respectively), but not for occupational status.

Conclusion

This study found a positive association between parental SES and skeletal muscle mass in Chinese college students. Compared to the normalization of height or weight, body mass index-adjusted skeletal muscle mass is more likely to be associated with SES.

Multifaceted Functions and Novel Insight Into the Regulatory Role of RNA N6-Methyladenosine Modification in Musculoskeletal Disorders

RNA modifications have emerged as key regulators of transcript expression in diverse physiological and pathological processes. As one of the most prevalent types of RNA modifications, N⁶-methyladenosine (m⁶A) has become the highlight in modulation of various diseases through interfering RNA splicing, translation, nuclear export, and decay. In many cases, the detailed functions of m⁶A in cellular processes and diseases remain unclear. Notably, recent studies have determined the relationship between m⁶A modification and musculoskeletal disorders containing osteosarcoma, osteoarthritis, rheumatoid arthritis, osteoporosis, etc. Herein, this review comprehensively summarizes the recent advances of m⁶A modification in pathogenesis and progression of musculoskeletal diseases. Specifically, the underlying molecular mechanisms, detection technologies, regulatory functions, clinical implications, and future perspectives of m⁶A in musculoskeletal disorders are discussed, with the aim to provide a novel insight into their association.

The association between FTO genotype with macronutrients and calorie intake in overweight adults

Background

Dietary macronutrients may indirectly affect body weight through their interactions with the fat mass and obesity associated (FTO) gene. This study aimed to investigate the association between FTO gene rs9939609 polymorphism with macronutrients intake in overweight adults.

Methods

This study was carried out on 196 overweight adults of Shiraz, Iran. Dietary intake was assessed using a validated 168-item semi-quantitative food frequency questionnaire (FFQ). The FTO gene was genotyped for rs9939609 polymorphism. The association between dietary macronutrients and the FTO genotype were assessed using linear regression after adjustments for sex, age, physical activity, and the serum levels of triglycerides, fasting blood sugar (FBS), and low density lipoprotein (LDL).

Results

The higher intake of carbohydrates (P < 0.001), fat (P = 0.009), and calorie (P = 0.001) were significantly associated with rs9939609 AA genotype (P = 0.001). Carriers of the AA genotype of rs9939609 had significantly higher calorie, fat, and carbohydrate intake than the carriers of the TT genotype after adjusting for age and sex (P = 0.019, P = 0.010 and P = 0.001, respectively). Further adjustments for physical activity, TG, LDL, and FBS did not change these results.

Conclusion

The amounts of dietary calorie, carbohydrate, and fat intake were associated with FTO genotype. Further studies are warranted to confirm these associations and to identify the underlying mechanisms.

Intracellular and tissue specific expression of FTO protein in pig: changes with age, energy intake and metabolic status

Genome-wide association studies in the FTO gene have identified SNPs correlating with obesity and type 2 diabetes. In mice, lack of Fto function leads to intrauterine growth retardation and lean phenotype, whereas in human it is lethal. The aim of this study in a pig model was to determine the localization of the FTO protein in different tissues and cell compartments, in order to investigate potential targets of FTO action. To better understand physiological role of FTO protein, its expression was studied in pigs of different age, metabolic status and nutrition, using both microscopic methods and Western blot analysis. For the first time, FTO protein was found in vivo in the cytoplasm, of not all, but specific tissues and cells e.g. in the pancreatic β-cells. Abundant FTO protein expression was found in the cerebellum, salivary gland and kidney of adult pigs. No FTO protein expression was detected in blood, saliva, and bile, excluding its role in cell-to-cell communication. In the pancreas, FTO protein expression was positively associated with energy intake, whereas in the muscles it was strictly age-related. In IUGR piglets, FTO protein expression was much higher in the cerebellum and kidneys, as compared to normal birth body weight littermates. In conclusion, our data suggest that FTO protein may play a number of distinct, yet unknown intracellular functions due to its localization. Moreover, it may play a role in animal growth/development and metabolic state, although additional studies are necessary to clarify the detailed mechanism(s) of action.

The critical roles of m6A modification in metabolic abnormality and cardiovascular diseases

N6-methyladenosine (m6A) RNA methylation is an emerging area of epigenetics, which is a reversible and dynamic modification mediating by ‘writers’ (methylase, adding methyl groups, METTL3, METTL14, and WTAP), ‘erasers’ (demethylase, deleting methyl groups, FTO and ALKBH5), and ‘readers’ (YTHDF1-3, YTHDC1 and YTHDC2). Recent studies in human, animal models and cell levels have disclosed a critical role of m6A modification in regulating the homeostasis of metabolic processes and cardiovascular function. Evidence from these studies identify m6A as a candidate of biomarker and therapeutic target for metabolic abnormality and cardiovascular diseases (CVD). Comprehensive understanding of the complexity of m6A regulation in metabolic diseases and CVD will be helpful for us to understand the pathogenesis of CVD. In this review, we discuss the regulatory role of m6A in metabolic abnormality and CVD. We will emphasize the clinical relevance of m6A dysregulation in CVD.

Effects of Breastfeeding and Formula Feeding on the Expression Level of FTO, CPT1A and PPAR-α Genes in Healthy Infants

PURPOSE

The study aimed to investigate the effect of breastfeeding, formula feeding and mix feeding (breastfed plus formula-fed) on the expression level of obesity-predisposing genes including fat mass and obesity-associated (FTO), carnitine palmitoyltransferase 1A (CPT1A), and peroxisome proliferator-activated receptor-α (PPAR-α) in 5- to 6-month-old infants.

PATIENTS AND METHODS

A total of 150 infants participated in this case-control study. All subjects were healthy infants aged 5-6 months that divided into 3 groups: breastfed, formula-fed, and mix-fed. The expression level of FTO, CPT1A, and PPAR-α genes in peripheral blood mononuclear cells (PBMC) was evaluated in each group using reverse transcription-polymerase chain reaction (RT-PCR) method.

RESULTS

Our findings showed that the current weight, height, and head circumference of infants in the formula feeding and mix feeding groups were significantly higher than those in the exclusive breastfeeding group. The expression level of FTO and CPT1A genes in formula-fed and mix-fed infants was significantly higher (p<0.001) than that in breastfed infants, while the expression level of PPAR-α gene was significantly lower (p<0.05).

CONCLUSION

Breastfeeding showed modulatory effects on the expression level of obesity-predisposing genes and can protect against obesity and subsequent non-communicable diseases. However, more investigations are required to explain the epigenetic effects of breast milk.