Sex differences in redox homeostasis in renal disease

Exploiting gender-based biomarkers and drug targets: advancing personalized therapeutic strategies in hepatocellular carcinoma

This review systematically examines gender differences in hepatocellular carcinoma (HCC), identifying the influence of sex hormones, genetic variance, and environmental factors on the disease's epidemiology and treatment outcomes. Recognizing the liver as a sexually dimorphic organ, we highlight how gender-specific risk factors, such as alcohol consumption and obesity, contribute differently to hepatocarcinogenesis in men and women. We explore molecular mechanisms, including the differential expression of androgen and estrogen receptors, which mediate diverse pathways in tumor biology such as cell proliferation, apoptosis, and DNA repair. Our analysis underscores the critical need for gender-specific research in liver cancer, from molecular studies to clinical trials, to improve diagnostic accuracy and therapeutic effectiveness. By incorporating a gender perspective into all facets of liver cancer research, we advocate for a more precise and personalized approach to cancer treatment that acknowledges gender as a significant factor in both the progression of HCC and its response to treatment. This review aims to foster a deeper understanding of the biological and molecular bases of gender differences in HCC and to promote the development of tailored interventions that enhance outcomes for all patients.

Association between oxidative balance score in adults with and without chronic kidney disease: 2011-2028 NHANES

Introduction

Oxidative stress status is associated with CKD; however, few studies have investigated this association. The oxidative balance score (OBS) reflects systemic stress status and consists of 16 anti-and pro-oxidant dietary factors and four anti-and pro-oxidant lifestyle factors. Higher OBS implies exposure to more antioxidants. The purpose of this study was to explore the association between OBS and CKD.

Methods

We enrolled 8,134 study participants from the 2011-2018 National Health and Nutrition Examination Survey and obtained OBS by adding the 20 dietary and lifestyle factors. Based on OBS, the participants were divided into three groups. We performed logistic regression, subgroup analyzes, and restricted cubic spline regression to explore the association between OBS and CKD. In addition, we tested the adjusted model.

Results

OBS was negatively associated with CKD (OR: 0.54; 0.66, 0.82). After adjusting for all confounders, when dietary OBS was >20, the prevalence of CKD was reduced by 42% for each unit increase in OBS (p < 0.05). The negative associations of total OBS, dietary OBS, and lifestyle OBS with CKD were more significant in the female group. When the total OBS was ~20, the trend of decreasing prevalence in the female group was more significant.

Conclusion

OBS is negatively associated with chronic kidney disease.

Sex as a biological variable in acute kidney injury

PURPOSE OF REVIEW

The purpose of this review is to provide an overview of the preclinical and clinical studies investigating sex as a biological variable, as well as the impact of gender, on the development of and progression of acute kidney injury (AKI).

RECENT FINDINGS

Despite a matched degree of ischemia-reperfusion AKI based on measured glomerular filtration rates, male and female mice demonstrated important sex biases in cardiorenal outcomes (1). Although the 2012 Kidney Disease Improving Global Outcomes (KDIGO) Clinical Practice Guideline for AKI reported that female sex is associated with increased rates of hospital acquired AKI, subsequent meta-analyses do not show increased risk of AKI in women. Recent large scale, multicenter epidemiologic studies suggest males have higher rates of hospital acquired AKI. However, women have been consistently shown to have worse renal outcomes after AKI. There may be also be gender-based differences in presentation to care and management.

SUMMARY

Sex is an important biological variable in animal models of acute kidney injury. The impact of sex on AKI likely varies based on the etiology of AKI. Preclinical studies demonstrate the nuances of sex chromosomes, sex hormones and epigenetic factors on AKI, however these have not been well studied in humans. Gender may also impact processes of care, treatment and clinical outcomes related to AKI. The scientific rigor and reproducibility of translational studies benefit from the consideration of sex and gender.

Salt Sensitivity of Blood Pressure in Women

Several clinical and large population studies indicate that women are more salt-sensitive than men, yet the precise mechanisms by which the sexually dimorphic onset manifests remains incompletely understood. Here, we evaluate recent epidemiological data and highlight current knowledge from studies investigating sex-specific mechanisms of salt-sensitive blood pressure (SSBP). Emerging evidence indicates that women of all ethnicities are more salt-sensitive than men, at all ages both premenopausal and postmenopausal. However, menopause exacerbates severity and prevalence of SSBP, suggesting that female sex chromosomes predispose to and female sex hormones mitigate SSBP. Results from both human and rodent studies support the contribution of enhanced and inappropriate activation of the aldosterone-ECMR (endothelial cell mineralocorticoid receptor) axis promoting vascular dysfunction in females. Increases in adrenal response to angiotensin II, in association with higher ECMR expression and activation of endothelial ENaC (epithelial sodium channel) in females compared to males, are emerging as central players in the development of endothelial dysfunction and SSBP in females. Female sex increases the prevalence and susceptibility of SSBP and sex hormones and sex chromosome complement may exert antagonistic effects in the development of the female heightened SSBP.

Forkhead box P3 gene polymorphisms predispose to type 2 diabetes and diabetic nephropathy in the Han Chinese populations: a genetic-association and gender-based evaluation study

BACKGROUND

Functional mutations or polymorphisms affecting forkhead box P3 (FOXP3) can lead to their abnormal FOXP3 gene expression and/or defective Treg cells generation, thus resulting in autoimmune disease and inflammatory disorders. FOXP3 also plays a key role in Type 2 diabetes mellitus (T2DM) and its complications, because the disease usually involves chronic low-grade inflammatory disorders and is associated with long-term immune system imbalance. This study aimed to investigate the association between FOXP3 polymorphisms and the susceptibility to T2DM and type 2 diabetes nephropathy (T2DN) within the Han Chinese populations.

METHODS

Polymorphisms in rs3761548C/A and rs2294021C/T were examined in 400 patients (which include an equal number of T2DM and T2DN groups) and 200 healthy controls using PCR-HRM and sequence analysis.

RESULTS

The genotype and allelic frequencies of the two single nucleotide polymorphisms (SNPs) were significantly different in T2DM and the progression of diabetes developing to T2DN. The further gender-based evaluation showed that in female subjects, rs3761548C/A was associated with an approximately 3-fold higher threat for T2DM and 4.5-fold for T2DN, while there was no noticeable association with rs2294021C/T; in males, the promoter polymorphism showed an increased predisposition of 5.4-fold and 3.4-fold predisposition to T2DM and T2DN, respectively, while rs2294021 polymorphism could impart a nearly 2-fold risk of developing T2DN. An additional analysis of combined genotypes (rs3761548 C/A-rs2294021C/T) revealed that CC-CC and CC-CT can be considered protective combinations in the predisposition of males with diabetes towards T2DN, while AA-CC and AA-TT have the opposite effect.

CONCLUSIONS

This study demonstrated the possible involvement of individual and combined genetic associations of rs3761548C/A and rs2294021C/T polymorphisms with the susceptibility to diabetes and diabetic nephropathy in the Han Chinese population, as well as gender bias.

Sex disparities and the risk of urolithiasis: a large cross-sectional study

BACKGROUND

Urolithiasis is one of the most common diseases in urology, with a lifetime prevalence of 14% and is more prevalent in males compared to females. We designed to explore sex disparities in the Chinese population to provide evidence for prevention measures and mechanisms of stone formation.

MATERIALS AND METHODS

A total of 98232 Chinese individuals who had undergone a comprehensive examination in 2017 were included. Fully adjusted odds ratios for kidney stones were measured using restricted cubic splines. Multiple imputations was applied for missing values. Propensity score matching was utilised for sensitivity analysis.

RESULTS

Among the 98232 included participants, 42762 participants (43.53%) were females and 55470 participants (56.47%) were males. Patients' factors might cast an influence on the development of kidney stone disease distinctly between the two genders. A risk factor for one gender might have no effect on the other gender. The risk for urolithiasis in females continuously rises as ageing, while for males the risk presents a trend to ascend until the age of around 53 and then descend.

CONCLUSIONS

Patients' factors might influence the development of kidney stones distinctly between the two genders. As age grew, the risk to develop kidney stones in females continuously ascended, while the risk in males presented a trend to ascend and then descend, which was presumably related to the weakening of the androgen signals.Key messagesWe found that patients' factors might cast an influence on the development of kidney stone disease distinctly between the two sexes.The association between age and urolithiasis presents distinct trends in the two sexesThe results will provide evidence to explore the mechanisms underlying such differences can cast light on potential therapeutic targets and promote the development of tailored therapy strategies in prospect.

Hypertension and renal disease programming: focus on the early postnatal period

The developmental origin of hypertension and renal disease is a concept highly supported by strong evidence coming from both human and animal studies. During development there are periods in which the organs are more vulnerable to stressors. Such periods of susceptibility are also called 'sensitive windows of exposure'. It was shown that as earlier an adverse event occurs; the greater are the consequences for health impairment. However, evidence show that the postnatal period is also quite important for hypertension and renal disease programming, especially in rodents because they complete nephrogenesis postnatally, and it is also important during preterm human birth. Considering that the developing kidney is vulnerable to early-life stressors, renal programming is a key element in the developmental programming of hypertension and renal disease. The purpose of this review is to highlight the great number of studies, most of them performed in animal models, showing the broad range of stressors involved in hypertension and renal disease programming, with a particular focus on the stressors that occur during the early postnatal period. These stressors mainly include undernutrition or specific nutritional deficits, chronic behavioral stress, exposure to environmental chemicals, and pharmacological treatments that affect some important factors involved in renal physiology. We also discuss the common molecular mechanisms that are activated by the mentioned stressors and that promote the appearance of these adult diseases, with a brief description on some reprogramming strategies, which is a relatively new and promising field to treat or to prevent these diseases.

Sex as a Biological Factor in the Changes in Disease Patients During Ramadan Intermittent Fasting: A Systematic Review

Background

During Ramadan, many patients with diabetes, renal, cardiovascular, gastrointestinal diseases, headaches, and epilepsy choose to fast even against their doctor's advice. The impact of this intermittent fasting on health and disease could be different in men and women. The aim of this study was to determine the effect of sex as a factor in diseases outcomes of patients who opt to fast during Ramadan.

Main Body

The articles included in this study reported data on six diseases: diabetes, renal, cardiovascular, gastrointestinal diseases, headaches, and epilepsy. A systematic search was performed on PubMed and Scopus for observational and clinical studies mentioning Ramadan, diabetes, renal, cardiovascular, gastrointestinal diseases, headaches, and epilepsy in both men and women. Data was extracted by two independent reviewers using a standardized data-collection form. From 381 original articles, 38 studies were selected, including 25,023 patients of which 44.4% were women. Sex-based differences were reported by 18 studies for several variables such as body mass index, blood glucose, the frequency of hypoglycemia, renal colic, mortality, thrombosis, and gastrointestinal diseases in patients fasting during Ramadan. Most of the differences between men and women were reported both in the baseline period before Ramadan and during Ramadan. Indeed, during the period outside Ramadan, the frequency of renal colic, cardiovascular, gastrointestinal diseases, were higher in men; while body mass index, Thrombosis, and headache were higher in women. In the remaining 21 studies, it was reported that the sex factor was not associated with the effect of Ramadan fasting in the frequency and other outcomes of these diseases.

Conclusion

Currently, small attention is paid to sex as a determinant factor in patients while fasting during Ramadan. There appeared to be differences in the frequency and incidence of diseases in men and women during Ramadan. Closer attention to sex differences regarding the frequency and the progression of the diseases during fasting may help to improve patient care, especially to benefit those patients willing to fast during Ramadan.

Impact of diabetes and ischemic stroke on the cerebrovasculature: A female perspective

There is a very complex interaction between the brain and the cerebral vasculature to meet the metabolic demands of the brain for proper function. Preservation of vascular networks and cerebrovascular function ultimately plays a key role in this intricate communication within the brain in health and disease. Experimental evidence showed that diabetes not only affects the architecture of cerebral blood arteries causing adverse remodeling, pathological neovascularization, and vasoregression, but also alters cerebrovascular function resulting in compromised myogenic reactivity and endothelial dysfunction. Coupled with the disruption of blood brain barrier (BBB) integrity, changes in blood flow and microbleeds into the brain can rapidly occur. When an ischemic insult is superimposed on this pathology, not only is the neurovascular injury greater, but repair mechanisms fail, resulting in greater physical and cognitive deficits. While clinically it is known that women suffer disproportionately from diabetes as well as ischemic stroke and post-stroke cognitive impairment, the cerebrovascular architecture, patho/physiology, as well as cerebrovascular contributions to stroke recovery in female and diabetic animal models are inadequately studied and highlighted in this review.

Sex Disparities in the Association of Serum Uric Acid With Kidney Stone: A Cross-Sectional Study in China

Background and Aims

Urolithiasis is characterized by high rates of prevalence and recurrence. Hyperuricemia is related to various diseases. We hope to determine the association between serum uric acid (UA) level and kidney stone (KS).

Methods

In this population-based cross-sectional study, a total of 82,017 Chinese individuals who underwent a comprehensive examination in 2017 were included. The KS was diagnosed based on ultrasonography examination outcomes. Fully adjusted odds ratio (OR) for KS, and mean difference between the two groups were applied to determine the association of UA level with KS.

Results

Among the 82,017 participants included in this study (aged 18~99 years), 9,435 participants (11.5%) are diagnosed with KS. A proportion of 56.3% of individuals is male. The mean UA level of overall participants is 341.77 μmol/L. The participants with KS report higher UA level than the participants without KS [mean UA level 369.91 vs. 338.11 μmol/L; mean difference (MD), 31.96 (95% CI, 29.61~34.28) μmol/L]. In men, the OR for KS significantly increases from 330 μmol/L UA level. Every 50 μmol/L elevation of UA level increases the risk of KS formation by about 10.7% above the UA level of 330 μmol/L in men. The subgroup analysis for male is consistent with the overall result except for the participants presenting underweight [adjusted OR, 1.035 (0.875~1.217); MD, −5.57 (−16.45~11.37)], low cholesterol [adjusted OR, 1.088 (0.938~1.261); MD, 8.18 (−7.93~24.68)] or high estimated glomerular filtration rate (eGFR) [adjusted OR, 1.044 (0.983~1.108); MD, 5.61 (−1.84~13.36)]. However, no significant association is observed in women between UA and KS either in all female participants or in female subgroups.

Conclusion

Among Chinese adults, UA level is associated with KS in a dose-response manner in men but not in women. However, the association becomes considerably weak in male participants with malnutrition status.

Nanotherapies for sepsis by regulating inflammatory signals and reactive oxygen and nitrogen species: New insight for treating COVID-19

SARS-CoV-2 has caused up to 127 million cases of COVID-19. Approximately 5% of COVID-19 patients develop severe illness, and approximately 40% of those with severe illness eventually die, corresponding to more than 2.78 million people. The pathological characteristics of COVID-19 resemble typical sepsis, and severe COVID-19 has been identified as viral sepsis. Progress in sepsis research is important for improving the clinical care of these patients. Recent advances in understanding the pathogenesis of sepsis have led to the view that an uncontrolled inflammatory response and oxidative stress are core factors. However, in the traditional treatment of sepsis, it is difficult to achieve a balance between the inflammation, pathogens (viruses, bacteria, and fungi), and patient tolerance, resulting in high mortality of patients with sepsis. In recent years, nanomaterials mediating reactive oxygen and nitrogen species (RONS) and the inflammatory response have shown previously unattainable therapeutic effects on sepsis. Despite these advantages, RONS and inflammatory response-based nanomaterials have yet to be extensively adopted as sepsis therapy. To the best of our knowledge, no review has yet discussed the pathogenesis of sepsis and the application of nanomaterials. To help bridge this gap, we discuss the pathogenesis of sepsis related to inflammation and the overproduction RONS, which activate pathogen-associated molecular pattern (PAMP)-pattern recognition receptor (PRR) and damage-associated molecular pattern (DAMP)-PRR signaling pathways. We also summarize the application of nanomaterials in the treatment of sepsis. As highlighted here, this strategy could synergistically improve the therapeutic efficacy against both RONS and inflammation in sepsis and may prolong survival. Current challenges and future developments for sepsis treatment are also summarized.

Cross-sex testosterone therapy modifies the renal morphology and function in female rats and might underlie increased systolic pressure

Testosterone esters are hormones commonly used for affirming gender identity in transmen. The present study evaluates the effect of testosterone on renal morphology and function in an animal model submitted to cross-sex hormone therapy used for transmen. Two-month-old Wistar rats were divided into three groups: male control (MC), female control (FC), and female on testosterone therapy (FTT). The FTT group received testosterone cypionate (3.0 mg/kg, i.m.), and the MC and MF groups received vehicle oil every 10 days for 4 months. Renal function and indirect systolic blood pressure (SBP) measurements were evaluated at 6 months of age. Plasma and urine concentrations of urea, creatinine, sodium, potassium, osmolality, and glomerular filtration rate (GFR) were measured. The kidneys were weighed, paraffin-embedded, and histological sections were prepared to evaluate the glomerular area. We verified that the FTT group, in comparison to FC, had increased kidney weight [MC, 3.2 ± 0.05; FC, 1.8 ± 0.04; FTT, 2.2 ± 0.06; g], decreased urine osmolarity [MC, 486.9 ± 18.3; FC, 1012.0 ± 5.4; FTT, 768.2 ± 40.3 mOsm/L/g kw], reduced GFR [MC, 0.77 ± 0.04; FC, 0.78 ± 0.02; FTT, 0.67 ± 0.03; mL/min/g kw], larger glomerular area [MC, 9334 ± 120.8; FC, 7884 ± 112.8; FTT, 9078 ± 133.4 µm2 ], and higher SBP [MC, 126 ± 3.4; FC, 119 ± 1.0; FTT, 131 ± 1.4; mmHg]. Sodium excretion was higher in FC and FTT in comparison to MC [MC, 0.34 ± 0.05; FC, 0.56 ± 0.06; FTT, 0.54 ± 0.04; mEq/24 h/g kw]. Cross-sex hormone therapy with testosterone in female rats induces renal morphofunctional changes and may underlie increased systolic pressure, suggesting an adaptation similar to what is observed in transmen on long-term testosterone therapy.

Sex differences in renal mitochondrial function: a hormone-gous opportunity for research

Sex differences (biological distinctions between males and females) present a complex interplay of genetic, developmental, biological, and environmental factors. More and more studies are shedding light on the importance of sex differences in normal physiology and susceptibility to cancer, cardiovascular and renal conditions, and neurodegenerative diseases. This mini-review is devoted to the role of sex dimorphisms in renal function, with a focus on the distinctions between male and female mitochondria. Here, we cover the aspects of renal mitochondrial bioenergetics where sex differences have been reported to date, for instance, biogenesis, reactive oxygen species production, and oxidative stress. Special attention is devoted to the effects of sex hormones, such as estrogen and testosterone, on mitochondrial bioenergetics in the kidney in physiology and pathophysiology.

Female Sex, a Major Risk Factor for Salt-Sensitive Hypertension

PURPOSE OF REVIEW

High dietary salt is a significant contributor to essential hypertension in clinical populations. However, although clinical studies indicate a higher prevalence of salt sensitivity in women over men, knowledge of salt-sensitive mechanisms is largely restricted to males, and female-specific mechanisms are presently being elucidated.

RECENT FINDINGS

Male-specific mechanisms of salt-sensitive hypertension are well published and predominantly appear to involve dysfunctional renal physiology. However, emerging novel evidence indicates that aldosterone production is sex-specifically heightened in salt-sensitive hypertensive women and female rodent models, which may be regulated by intra-adrenal renin-angiotensin system activation and sex hormone receptors. In addition, new evidence that young females endogenously express higher levels of endothelial mineralocorticoid receptors (MRs) and that endothelial MR is a crucial mediator of endothelial dysfunction in females indicates that the aldosterone-endothelial MR activation pathway is a novel mediator of salt-sensitive hypertension. Heightened aldosterone levels and endothelial MR expression provide a 2-fold sex-specific mechanism that may underlie the pathology of salt-sensitive hypertension in women. This hypothesis indicates that MR antagonists may be a preferential treatment for premenopausal women diagnosed with salt-sensitive hypertension.

An investigation into the impact of deleting one copy of the glutaredoxin-2 gene on diet-induced weight gain and the bioenergetics of muscle mitochondria in female mice fed a high fat diet

Our group recently documented that male mice containing a deletion for one copy of the glutaredoxin-2 (Grx2) gene were completely protected from developing diet-induced obesity (DIO). Objectives: Here, we conducted a similar investigation but with female littermates. Results: In comparison to our recent publication using male mice, exposure of WT and GRX2+/- female mice to a HFD from 3-to-10 weeks of age did not induce any changes in body mass, circulating blood glucose, food intake, hepatic glycogen levels, or abdominal fat pad mass. Examination of the bioenergetics of muscle mitochondria revealed no changes in the rate of superoxide ( O 2 ∙ - )/hydrogen peroxide (H₂O₂) or O₂ consumption under different states of respiration or alterations in lipid peroxidation adduct levels regardless of mouse strain or diet. Additionally, we measured the bioenergetics of mitochondria isolated from liver tissue and found that partial loss of GRX2 augmented respiration but did not alter ROS production. Discussion: Overall, our findings demonstrate there are sex differences in the protection of female GRX2+/- mice from DIO, fat accretion, intrahepatic lipid accumulation, and the bioenergetics of mitochondria from muscle and liver tissue.

Gender differences in the susceptibility of hospital-acquired acute kidney injury: more questions than answers

Hospital-acquired acute kidney injury (HA-AKI) is a heterogeneous renal syndrome which occurs in different clinical settings. It is characterized by multiple aetiologies, various pathogeneses and unpredictable outcomes. HA-AKI, once predominantly viewed as a self-limited and reversible short-term condition, is now recognized as a harbinger for chronic kidney disease and a cause of long-term morbidity with an increased risk of cardiovascular, renal and cancer mortality. Recent clinical studies contradict the generally held belief that female sex is a risk factor for HA-AKI. They show, consistent with basic research performed with experimental models of AKI, that only male sex is associated with HA-AKI. The presence of testosterone, more likely than the absence of estrogen, plays a critical role in sex differences in the susceptibility of ischemia/reperfusion kidney injury. The conflicting data in epidemiological studies related to sex as susceptibility variable for human AKI, underscore the need for more rigorous, well designed observational studies taking into account the menopausal status and hormone therapy.

An Update on Mitochondrial Reactive Oxygen Species Production

Mitochondria are quantifiably the most important sources of superoxide (O₂^●-) and hydrogen peroxide (H₂O₂) in mammalian cells. The overproduction of these molecules has been studied mostly in the contexts of the pathogenesis of human diseases and aging. However, controlled bursts in mitochondrial ROS production, most notably H₂O₂, also plays a vital role in the transmission of cellular information. Striking a balance between utilizing H₂O₂ in second messaging whilst avoiding its deleterious effects requires the use of sophisticated feedback control and H₂O₂ degrading mechanisms. Mitochondria are enriched with H₂O₂ degrading enzymes to desensitize redox signals. These organelles also use a series of negative feedback loops, such as proton leaks or protein S-glutathionylation, to inhibit H₂O₂ production. Understanding how mitochondria produce ROS is also important for comprehending how these organelles use H₂O₂ in eustress signaling. Indeed, twelve different enzymes associated with nutrient metabolism and oxidative phosphorylation (OXPHOS) can serve as important ROS sources. This includes several flavoproteins and respiratory complexes I-III. Progress in understanding how mitochondria generate H₂O₂ for signaling must also account for critical physiological factors that strongly influence ROS production, such as sex differences and genetic variances in genes encoding antioxidants and proteins involved in mitochondrial bioenergetics. In the present review, I provide an updated view on how mitochondria budget cellular H₂O₂ production. These discussions will focus on the potential addition of two acyl-CoA dehydrogenases to the list of ROS generators and the impact of important phenotypic and physiological factors such as tissue type, mouse strain, and sex on production by these individual sites.