Sufficient Plasma Vitamin C Is Related to Greater Bone Mineral Density among Postmenopausal Women from the Boston Puerto Rican Health Study

Role of oxidative stress in the concurrent development of osteoporosis and tendinopathy: Emerging challenges and prospects for treatment modalities

Both osteoporosis and tendinopathy are widely prevalent disorders, encountered in diverse medical contexts. Whilst each condition has distinct pathophysiological characteristics, they share several risk factors and underlying causes. Notably, oxidative stress emerges as a crucial intersecting factor, playing a pivotal role in the onset and progression of both diseases. This imbalance arises from a dysregulation in generating and neutralising reactive oxygen species (ROS), leading to an abnormal oxidative environment. Elevated levels of ROS can induce multiple cellular disruptions, such as cytotoxicity, apoptosis activation and reduced cell function, contributing to tissue deterioration and weakening the structural integrity of bones and tendons. Antioxidants are substances that can prevent or slow down the oxidation process, including Vitamin C, melatonin, resveratrol, anthocyanins and so on, demonstrating potential in treating these overlapping disorders. This comprehensive review aims to elucidate the complex role of oxidative stress within the interlinked pathways of these comorbid conditions. By integrating contemporary research and empirical findings, our objective is to outline new conceptual models and innovative treatment strategies for effectively managing these prevalent diseases. This review underscores the importance of further in-depth research to validate the efficacy of antioxidants and traditional Chinese medicine in treatment plans, as well as to explore targeted interventions focused on oxidative stress as promising areas for future medical advancements.

Daily yogurt consumption does not affect bone turnover markers in men and postmenopausal women of Caribbean Latino descent: a randomized controlled trial

BACKGROUND

Caribbean Latino adults are at high risk for osteoporosis yet remain underrepresented in bone research. This increased risk is attributed to genetics, diet, and lifestyle known to drive inflammation and microbial dysbiosis.

OBJECTIVE

The primary objective of this study was to determine whether consuming 5 oz of yogurt daily for 8wks improves bone turnover markers (BTMs) among Caribbean Latino adults > 50 years; and secondarily to determine the impact on the gut microbiota and markers of intestinal integrity and inflammation.

METHODS

Following a 4wk baseline period, participants were randomized to an 8wk whole fat yogurt intervention (n = 10) daily, containing only Streptococcus thermophilus and Lactobacillus bulgaricus, or to an untreated control group that did not consume yogurt (n = 10). Blood and stool samples collected at week-0 and week-8 were used to assess BTMs, inflammation, intestinal integrity biomarkers, and gut microbiota composition, short chain fatty acids (SCFAs), respectively. Data were evaluated for normality and statistical analyses were performed.

RESULTS

Participants were 55% women, with a mean age of 70 ± 9 years, BMI 30 ± 6 kg/m2, and serum C-reactive protein 4.8 ± 3.6 mg/L, indicating chronic low-grade inflammation. Following 8wks of yogurt intake, absolute change in BTMs did not differ significantly between groups (P = 0.06-0.78). Secondarily, absolute change in markers of inflammation, intestinal integrity, and fecal SCFAs did not differ significantly between groups (P range 0.13-1.00). Yogurt intake for 8wks was significantly associated with microbial compositional changes of rare taxa (P = 0.048); however, no significant alpha diversity changes were observed.

CONCLUSIONS

In this study, daily yogurt did not improve BTMs, inflammation, intestinal integrity, nor SCFAs. However, yogurt did influence beta diversity, or the abundance of rare taxa within the gut microbiota of the yogurt group, compared to controls. Additional research to identify dietary approaches to reduce osteoporosis risk among Caribbean Latino adults is needed.

TRIAL REGISTRATION

This study is registered to ClinicalTrials.gov, NCT05350579 (28/04/2022).

Role of vitamins beyond vitamin D3 in bone health and osteoporosis (Review)

The objective of the present review was to summarize the molecular mechanisms associated with the effects of the vitamins A, C, E and K, and group B vitamins on bone and their potential roles in the development of osteoporosis. Epidemiological findings have demonstrated an association between vitamin deficiency and a higher risk of developing osteoporosis; vitamins are positively related to bone health upon their intake at the physiological range. Excessive vitamin intake can also adversely affect bone formation, as clearly demonstrated for vitamin A. Vitamins E (tocopherols and tocotrienols), K2 (menaquinones 4 and 7) and C have also been shown to promote osteoblast development through bone morphogenetic protein (BMP)/Smad and Wnt/β‑catenin signaling, as well as the TGFβ/Smad pathway (α‑tocopherol). Vitamin A metabolite (all‑trans retinoic acid) exerts both inhibitory and stimulatory effects on BMP‑ and Wnt/β‑catenin‑mediated osteogenesis at the nanomolar and micromolar range, respectively. Certain vitamins significantly reduce receptor activator of nuclear factor kappa‑B ligand (RANKL) production and RANKL/RANK signaling, while increasing the level of osteoprotegerin (OPG), thus reducing the RANKL/OPG ratio and exerting anti‑osteoclastogenic effects. Ascorbic acid can both promote and inhibit RANKL signaling, being essential for osteoclastogenesis. Vitamin K2 has also been shown to prevent vascular calcification by activating matrix Gla protein through its carboxylation. Therefore, the maintenance of a physiological intake of vitamins should be considered as a nutritional strategy for the prevention of osteoporosis.

Vitamin C Urinary Loss and Deficiency in Human Immunodeficiency Virus (HIV): Cross-sectional Study of Vitamin C Renal Leak in Women With HIV

BACKGROUND

Reduced plasma vitamin C (vitC) concentrations in human immunodeficiency virus (HIV) may result from abnormal urinary excretion: a renal leak. VitC renal leak indicates underlying nutritional dysregulation independent of diet. We hypothesized that increased renal leak prevalence in HIV would be associated with deficient vitC concentrations.

METHODS

We conducted an outpatient cross-sectional study of 96 women (40 HIV [PWH] and 56 without HIV [PWOH]) at the National Institutes of Health and Georgetown University. Renal leak was defined as abnormal urinary vitC excretion at fasting plasma concentrations <43.2µM, 2 SDs below vitC renal threshold in healthy women. To determine the primary outcome of renal leak prevalence, matched urine and plasma samples were collected the morning after overnight fast. Secondary outcomes assessed group differences in mean plasma vitC concentrations and prevalence of vitC deficiency. Exploratory outcomes assessed clinical parameters associated with renal leak. VitC was measured by high-performance liquid chromatography with coulometric electrochemical detection.

RESULTS

PWH had significantly higher renal leak prevalence (73%vs14%; OR (odds ratio):16; P<.001), lower mean plasma vitC concentrations (14µMvs50µM; P<.001), and higher prevalence of vitC deficiency (43%vs7%; OR:10; P<.001) compared with PWOH, unchanged by adjustments for confounding factors. Significant predictors of renal leak included antiretroviral therapy (ART), Black race, older age, and metabolic comorbidities but not viral load or CD4 count. When compared with other chronic disease cohorts, PWH had the highest prevalence of renal leak and vitC deficiency (P<.001).

CONCLUSIONS

High prevalence of vitC renal leak in HIV was associated with vitC deficiency, ART use, and race/ethnicity differences.

Examining the Health-Related Needs of Females during Menopause: A Systematic Review Study

Menopause is one the most crucial stages in a female's life. Identifying the education gaps regarding menopause is important, thus this study aims to explain the health-related needs of females during menopause. Scopus, PubMed, Scientific Information Database, and Web of Science databases were searched for the available observational (cohort, case-control, and cross-sectional), systematic review, meta-analysis, and clinical trial studies (2007-2021) using keywords, such as 'Educational Needs Assessment,' 'Assessment of Healthcare Needs,' 'menopause,' 'climacteric,' 'premenopause,' and 'postmenopause.' A total of 180 out of 5,705 papers were evaluated after considering the inclusion and exclusion criteria. The educational needs of females during menopause in the reviewed studies include osteoporosis, oral and dental problems, metabolic disorders, cardiovascular diseases, hypertension, lung diseases, infectious diseases, musculoskeletal problems, urinary problems, breast cancer, defecation problems, genital disorders, special diseases such as eye diseases and hypothyroidism and hormone therapy, mental disorders, cognitive function, sleep disorders, sexual disorders, physical activity, supplement consumption, public health issues, health education, fall, and nutrition. The study results reveal that females during postmenopause require training, counseling, and support in all aspects to get through this challenging time, and providing these services, infrastructure, appropriate policy, and the use and support of the medical team's capacity are all required.

Suboptimal Plasma Vitamin C Is Associated with Lower Bone Mineral Density in Young and Early Middle-Aged Men: A Retrospective Cross-Sectional Study

Background: This study was conducted to evaluate associations between bone mineral density (BMD) and four selected circulating nutrients, particularly vitamin C, among adults aged 20−49 years. Methods: In this retrospective cross-sectional study, the lumbar spine BMD of 866 men and 589 women were measured by dual-energy X-ray absorptiometry and divided into tertiles, respectively. Logistic regressions were used to identify the predictors of low BMD by comparing subjects with the highest BMD to those with the lowest. Results: Multivariate logistic regressions identified suboptimal plasma vitamin C (adjusted odds ratio (AOR) 1.64, 95% confidence interval (CI) 1.16, 2.31), suboptimal serum vitamin B12 (AOR 2.05, 95% CI 1.02, 4.12), and low BMI (BMI < 23) (AOR 1.68, 95% CI 1.12, 2.53) as independent predictors for low BMD in men. In women, low BMI was the only independent predictor for low BMD. Plasma vitamin C, categorized as suboptimal (≤8.8 mg/L) and sufficient (>8.8 mg/L), was positively significantly correlated with the lumbar spine BMD in men, but there was no association in women. Conclusions: Plasma vitamin C, categorized as suboptimal and sufficient, was positively associated with the lumbar spine BMD in young and early middle-aged men. A well-designed cohort study is needed to confirm the findings.