Peripubertal Bisphenol A Exposure Imparts Detrimental Age-Related Changes in Body Composition, Cognition, and Hydrogen Sulfide Production Capacities

Melatonin Rescues Renal Mitochondria From Multiple Stressors-Induced Oxidative Stress

The renal system is a significant organ system vulnerable to stress due to its physiological function of toxin elimination. Exposure to a wide array of xenobiotics in humans causes deleterious effects in the kidneys. In the present study, we observed the toxic effect of a coexposure of bisphenol A and acetaminophen on the renal function and renal mitochondria of Wistar rats and its amelioration by melatonin. The animals were grouped and treated for 4 weeks as follows: (I) control; (II) melatonin; (III) bisphenol A; (IV) acetaminophen; (V) bisphenol A and acetaminophen; and (VI) bisphenol A, acetaminophen and melatonin. Coadministration of bisphenol A and acetaminophen exposure significantly impaired renal function, elevating creatinine (2.28 mg/dL), BUN (65.42 mg/dL) and uric acid (6.11 mg/dL), while increasing oxidative stress and inflammatory markers (CAT: 3.85-μmol H2O2/min/mg protein, GPx: 189.57-nmol NADPH/min/mg protein, GR: 96.62-nmol NADPH/min/mg protein, MnSOD: 107.24-nmol (-) epinephrine/min/mg protein, IL-6: 1750 pg/mL, TNFα: 1677 pg/mL). Melatonin coadministration improved renal markers (creatinine: 1.60 mg/dL, BUN: 45.59 mg/dL, uric acid: 4.61 mg/dL) and partially restored antioxidant defences and inflammatory markers (CAT: 5.74-μmol H2O2/min/mg protein, GPx: 422.74-nmol NADPH/min/mg protein, GR: 136.91-nmol NADPH/min/mg protein, MnSOD: nmol (-) epinephrine prevented from oxidation/min/mg protein, IL-6: 1677 pg/mL, TNFα: 900 pg/mL). These findings suggest that melatonin mitigates bisphenol A and acetaminophen-induced renal damage by enhancing antioxidant defences and reducing inflammation.

Early-life bisphenol A exposure causes detrimental age-related changes in anxiety, depression, learning, and memory in juvenile and adult male rats: Involvement of NMDAR/PSD-95-PTEN/AKT signaling pathway

Bisphenol A (BPA) is an endocrine disruptor monomer that is widely used in the manufacturing of epoxy resins and polycarbonate plastics. Several lines of evidence indicate the function of the pre- or perinatally PI3K/AKT signaling pathway in the development of psychiatric disorders. The present study aimed to evaluate for the first time the effect of modifying the NMDAR/PSD-95-PTEN/AKT signaling pathway on behavioral and synaptic plasticity of early-life BPA exposure and its long-lasting influence on juvenile and adulthood stages of development. We investigated the effects of oral BPA doses of 50 and 125 mg/kg/day on the prefrontal cortex (PFC) and hippocampus of male Sprague Dawley rats from postnatal day (PND) 18-60 and PND 18-95, which correspond to juvenile and adolescent stages, respectively. Subsequently, we performed a series of rat behavioral tests, including the open field, elevated plus-maze, forced swimming, and Y-maze. Notably, neurotransmitter levels such as dopamine, serotonin, and gamma-aminobutyric acid, levels of postsynaptic density protein 95 and cAMP response element-binding protein, as well as mRNA levels of N-methyl-D-aspartate receptor subunits, fluctuated between reduction and elevation in the PFC and hippocampus. Furthermore, phosphatase and tensin (PTEN) mRNA and protein levels were upregulated in both brain areas, while PI3K, protein kinase B (AKT) and mammalian target of rapamycin (mTOR) mRNA and protein levels were decreased. Finally, our findings indicate that postnatal BPA exposure promotes long-term anxiety and depressive-like behaviors, as well as cognitive impairment, via modulation of the NMDAR/PSD-95-PTEN/AKT pathway. These findings could help to elucidate the potential developmental and neurobehavioral effects of early-life BPA exposure.

Bisphenol A (BPA) and neurological disorders: An overview

The human body is commonly exposed to bisphenol A (BPA), which is widely used in consumer and industrial products. BPA is an endocrine-disrupting chemical that has adverse effects on human health. In particular, many studies have shown that BPA can cause various neurological disorders by affecting brain development and neural function during prenatal, infancy, childhood, and adulthood exposure. In this review, we discussed the correlation between BPA and neurological disorders based on molecular cell biology, neurophysiology, and behavioral studies of the effects of BPA on brain development and function. Recent studies, both animal and epidemiological, strongly indicate that BPA significantly impacts brain development and function. It hinders neural processes, such as proliferation, migration, and differentiation during development, affecting synaptic formation and activity. As a result, BPA is implicated in neurodevelopmental and neuropsychiatric disorders like autism spectrum disorder (ASD), attention-deficit hyperactivity disorder (ADHD), and schizophrenia.

Global approaches for protein thiol redox state detection

Due to its nucleophilicity, the thiol group of cysteine is chemically very versatile. Hence, cysteine often has important functions in a protein, be it as the active site or, in extracellular proteins, as part of a structural disulfide. Within the cytosol, cysteines are typically reduced. But the nucleophilicity of its thiol group makes it also particularly prone to post-translational oxidative modifications. These modifications often lead to an alteration of the function of the affected protein and are reversible in vivo, e.g. by the thioredoxin and glutaredoxin system. The in vivo-reversible nature of these modifications and their genesis in the presence of localized high oxidant levels led to the paradigm of thiol-based redox regulation, the adaptation, and modulation of the cellular metabolism in response to oxidative stimuli by thiol oxidation in regulative proteins. Consequently, the proteomic study of these oxidative posttranslational modifications of cysteine plays an indispensable role in redox biology.

Association Between Urinary Bisphenols and Body Composition Among American Adults: Cross-Sectional National Health and Nutrition Examination Survey Study

BACKGROUND

Bisphenol A (BPA), bisphenol S (BPS), and bisphenol F (BPF) are widely used in various consumer products. They are environmental contaminants with estrogenic properties that have been linked to various health outcomes. Understanding their impact on body composition is crucial for identifying potential health risks and developing preventive strategies. However, most current studies have only focused on their relationship with BMI.

OBJECTIVE

This study aimed to investigate the association between urinary levels of BPA, BPS, and BPF and body composition, including BMI, lean mass, and fat mass, in a large population-based sample.

METHODS

We conducted a cross-sectional analysis using data from the National Health and Nutrition Examination Survey 2003-2016. Body composition data were assessed using dual-energy X-ray absorptiometry, which provided precise measurements of lean mass, fat mass, and other indicators. We used multivariate linear regression models to estimate the associations, adjusting for potential confounders such as age, gender, race, socioeconomic factors, and lifestyle variables.

RESULTS

The results revealed significant associations between bisphenol exposure and body composition. After adjusting for covariates, BPS showed a positive association with BMI, with quartiles 3 and 4 having 0.91 (95% CI 0.34-1.48) and 1.15 (95% CI 0.55-1.74) higher BMI, respectively, compared with quartile 1 (P<.001). BPA was negatively associated with total lean mass (TLM) and appendicular lean mass, with quartiles 2, 3, and 4 having -7.85 (95% CI -11.44 to -4.25), -12.33 (95% CI -16.12 to -8.54), and -11.08 (95% CI -15.16 to -7.01) lower TLM, respectively, compared with quartile 1 (P<.001). BPS was negatively associated with TLM, with quartiles 3 (β=-10.53, 95% CI -16.98 to -4.08) and 4 (β=-11.14, 95% CI -17.83 to -4.45) having significantly lower TLM (P=.005). Both BPA and BPS showed a positive dose-response relationship with trunk fat (BPA: P=.002; BPS: P<.001) and total fat (BPA: P<.001; BPS: P=.01). No significant association was found between BPF and any body composition parameter.

CONCLUSIONS

This large-sample study highlights the associations between urinary levels of BPA and BPS and alterations in body composition, including changes in lean mass, fat mass, and regional fat distribution. These findings underscore the importance of understanding the potential health risks associated with bisphenol exposure and emphasize the need for targeted interventions to mitigate adverse effects on body composition.

A long-term obesogenic high-fat diet in mice partially dampens the anti-frailty benefits of late-life intermittent fasting

The global obesity pandemic coupled with ever-growing life expectancies equates to hundreds of millions of individuals with potentially longer but not healthier lives. Aging is one of the risk factors for numerous maladies such as metabolic disorder and frailty, which are exacerbated under obesity. Thus, therapeutic approaches that address obesity to ultimately improve affected individuals' quality of life and extend their lifespan are needed. We previously reported that the every other day (EOD) fasting initiated late-life improved metabolic, musculoskeletal, and cognitive endpoints in standard rodent diet-fed mice. In the present study, using the same dietary intervention methodology, we tested if 2.5 months of EOD fasting could improve metabolic, physiological, and cognitive endpoints in mice after an 18 month obesogenic high-fat diet (HFD). The positive effects of EOD fasting were generally consistent across the endpoints; EOD fasting decreased total body mass, maintained more %lean mass, improved glucose tolerance and utilization, and improved neuromuscular function. In contrast to our previous study, grip strength, hippocampal-dependent memory, and renal hydrogen sulfide (H₂S) production were not improved by the HFD EOD fasting. Thus, efficacy for late-life initiated intermittent fasting to improve specific frailty markers may be partially dependent on nutritional compositions of the diet.

Sulfur Amino Acid Supplementation Abrogates Protective Effects of Caloric Restriction for Enhancing Bone Marrow Regrowth Following Ionizing Radiation

Radiation therapy damages and depletes total bone marrow (BM) cellularity, compromising safety and limiting effective dosing. Aging also strains total BM and BM hematopoietic stem and progenitor cell (HSPC) renewal and function, resulting in multi-system defects. Interventions that preserve BM and BM HSPC homeostasis thus have potential clinical significance. Here, we report that 50% calorie restriction (CR) for 7-days or fasting for 3-days prior to irradiation improved mouse BM regrowth in the days and weeks post irradiation. Specifically, one week of 50% CR ameliorated loss of total BM cellularity post irradiation compared to ad libitum-fed controls. CR-mediated BM protection was abrogated by dietary sulfur amino acid (i.e., cysteine, methionine) supplementation or pharmacological inhibition of sulfur amino acid metabolizing and hydrogen sulfide (H₂S) producing enzymes. Up to 2-fold increased proliferative capacity of ex vivo-irradiated BM isolated from food restricted mice relative to control mice indicates cell autonomy of the protective effect. Pretreatment with H₂S in vitro was sufficient to preserve proliferative capacity by over 50% compared to non-treated cells in ex vivo-irradiated BM and BM HSPCs. The exogenous addition of H₂S inhibited Ten eleven translocation 2 (TET2) activity in vitro, thus providing a potential mechanism of action. Short-term CR or fasting therefore offers BM radioprotection and promotes regrowth in part via altered sulfur amino acid metabolism and H₂S generation, with translational implications for radiation treatment and aging.

Protein S-sulfhydration: Unraveling the prospective of hydrogen sulfide in the brain, vasculature and neurological manifestations

Hydrogen sulfide (H₂S) and hydrogen polysulfides (H₂S_n) are essential regulatory signaling molecules generated by the entire body, including the central nervous system. Researchers have focused on the classical H₂S signaling from the past several decades, whereas the last decade has shown the emergence of H₂S-induced protein S-sulfhydration signaling as a potential therapeutic approach. Cysteine S-persulfidation is a critical paradigm of post-translational modification in the process of H₂S signaling. Additionally, studies have shown the cross-relationship between S-sulfhydration and other cysteine-induced post-translational modifications, namely nitrosylation and carbonylation. In the central nervous system, S-sulfhydration is involved in the cytoprotection through various signaling pathways, viz. inflammatory response, oxidative stress, endoplasmic reticulum stress, atherosclerosis, thrombosis, and angiogenesis. Further, studies have demonstrated H₂S-induced S-sulfhydration in regulating different biological processes, such as mitochondrial integrity, calcium homeostasis, blood-brain permeability, cerebral blood flow, and long-term potentiation. Thus, protein S-sulfhydration becomes a crucial regulatory molecule in cerebrovascular and neurodegenerative diseases. Herein, we first described the generation of intracellular H₂S followed by the application of H₂S in the regulation of cerebral blood flow and blood-brain permeability. Further, we described the involvement of S-sulfhydration in different biological and cellular functions, such as inflammatory response, mitochondrial integrity, calcium imbalance, and oxidative stress. Moreover, we highlighted the importance of S-sulfhydration in cerebrovascular and neurodegenerative diseases.