High Fat High Sugar Diet Reduces Small Intestinal Secretion by Sex-Dependent Mechanisms.

BACKGROUND/AIMS: The goal of this study was to determine the influence of high-fat high-sugar diet (Western diet) on intestinal function and subsequently to determine if there were any beneficial effects of exercise, genistein (a naturally occurring phytoestrogen) or both, on the intestine. METHODS: We measured transepithelial short circuit current (Isc), across freshly isolated segments of jejunum from male and female C57Bl/6J mice randomly assigned to one of the following groups for the 12-week study duration: high-fat high-sugar diet (HFS), HFS with genistein (Gen), HFS with exercise (Ex), or HFS with both genistein and exercise (Gen+Ex) and compared them to lean controls. Genistein concentration was 600 mg genistein/kg diet. Exercise comprised of moderate intensity treadmill running (150 min per week). At the completion of the study, segments of jejunum were frozen for western blot determination of key proteins involved in secretory and absorptive functions, as well as senescence. Intestinal morphology was assessed. Serum cytokine assays were performed. RESULTS: Basal Isc was significantly decreased (by 70%, P<0.05) in HFS females and males versus leans. This decrease was partially mitigated by exercise in both sexes. In females, the HFS-induced decrease in Isc was attributed to a significant loss of CLC2, NKCC1 and CFTR expression whereas in males this was due to a significant loss of Na/K-ATPase, KCa and NKCC1 expression (indicating sex-dependent mechanisms). Exercise mitigated most of the loss of Isc in both sexes. Our data suggested that A2BR levels were dysregulated in HFS fed mice and that concomitant treatment with Gen or Gen+Ex prevented this disruption in females only. Inflammatory state was associated with body weight changes. CONCLUSION: Our data suggests that the reduced basal jejunal Isc in HFS mice is attributed to sex-dependent mechanisms and while exercise partially mitigated this, it's mechanism of action was unclear. Improved understanding of Western diet induced intestinal dysfunctions may allow for the development of novel drug targets to treat gastrointestinal disturbances in diabetic obesity.

Systematic review of the impact of genistein on diabetes-related outcomes.

Diabetes is the eighth leading cause of death in the world and the prevalence is rising in low-income countries. Cardiovascular diseases are the leading cause of death worldwide, especially for individuals with diabetes. Although medications exist to treat symptoms of diabetes, lack of availability and high costs may deter their use by individuals with low incomes as well as those in low-income nations. Therefore, this systematic review was performed to determine whether genistein, a phytoestrogen found in soy products, could provide therapeutic benefits for individuals with diabetes. We searched PubMed and SCOPUS using the terms "genistein," "diabetes," and "glucose" and identified 33 peer-reviewed articles that met our inclusion criteria. In general, preclinical studies demonstrated that genistein decreases body weight and circulating glucose and triglycerides concentrations, whereas increasing insulin levels and insulin sensitivity. Genistein also delayed the onset of type 1 and type 2 diabetes. In contrast, clinical studies utilizing genistein generally reported no significant relationship between genistein and body mass, circulating glucose, glycated hemoglobin (A1C) concentrations, or onset of type 1 diabetes. However, genistein was found to improve insulin sensitivity and serum triglyceride concentrations and delayed the onset of type 2 diabetes. In summary, preclinical and clinical studies suggest that genistein may help delay the onset of type 2 diabetes and improve several symptoms associated with the disease. Although additional research is required to confirm these findings, the results highlighted in this review provide some evidence that genistein may offer a natural approach to mitigating some of the complications associated with diabetes.

Neuroprotective Effects of Chronic Resveratrol Treatment and Exercise Training in the 3xTg-AD Mouse Model of Alzheimer's Disease.

To date, there is no cure or effective treatment for Alzheimer's disease (AD), a chronic neurodegenerative condition that affects memory, language, and behavior. AD is characterized by neuroinflammation, accumulation of brain amyloid-beta (Aß) oligomers and neurofibrillary tangles, increased neuronal apoptosis, and loss of synaptic function. Promoting regular exercise and a diet containing polyphenols are effective non-pharmacological approaches that prevent the progression of neurodegenerative diseases. In this study, we measured various conformational toxic species of Aß and markers of inflammation, apoptosis, endolysosomal degradation, and neuroprotection after 5 months of exercise training (ET), resveratrol (Resv) treatment, or combination treatment in the 3xTg-AD mouse model of AD. Our main results indicate that Resv decreased neuroinflammation and accumulation of Aß oligomers, increased levels of neurotrophins, synaptic markers, silent information regulator, and decreased markers of apoptosis, autophagy, endolysosomal degradation and ubiquitination in the brains of 3xTg-AD mice. ET improved some markers related to neuroprotection, but when combined with Resv treatment, the benefits achieved were as effective as Resv treatment alone. Our results show that the neuroprotective effects of Resv, ET or Resv and ET are associated with reduced toxicity of Aß oligomers, suppression of neuronal autophagy, decreased apoptosis, and upregulation of key growth-related proteins.

Effects of Exercise Training on Renal Carnitine Biosynthesis and Uptake in the High-Fat and High-Sugar-Fed Mouse.

(1) Background: Diet-induced obesity inhibits hepatic carnitine biosynthesis. Herein, the effects of high-fat (HF) and high-sugar (HFHS) feeding and exercise training (ET) on renal carnitine biosynthesis and uptake were determined. (2) Methods: Male C57BL/6J mice were assigned to the following groups: lean control (standard chow), HFHS diet, and HFHS diet with ET. ET consisted of 150 min of treadmill running per week for 12 weeks. Protein levels of γ-butyrobetaine hydroxylase (γ-BBH) and organic cation transporter-2 (OCTN2) were measured as markers of biosynthesis and uptake, respectively. (3) Results: HFHS feeding induced an obese diabetic state with accompanying hypocarnitinemia, reflected by decreased free carnitine levels in plasma and kidney. This hypocarnitinemia was associated with decreased γ-BBH (~30%) and increased OCTN2 levels (~50%). ET failed to improve the obesity and hyperglycemia, but improved insulin levels and prevented the hypocarnitinemia. ET increased protein levels of γ-BBH, whereas levels of OCTN2 were decreased. Peroxisome proliferator-activated receptor-alpha content was not changed by the HFHS diet or ET. (4) Conclusions: Our results indicate that ET prevents the hypocarnitinemia induced by HFHS feeding by increasing carnitine biosynthesis in kidney. Increased expression of OCTN2 with HFHS feeding suggests that renal uptake was stimulated to prevent carnitine loss.

Exercise and resveratrol increase fracture resistance in the 3xTg-AD mouse model of Alzheimer's disease.

BACKGROUND: Alzheimer's disease (AD) and osteoporosis are progressive diseases that affect the elderly population. Both conditions are associated with fracture risk that is greater than twice that of the healthy population. Resveratrol and exercise are two treatments that have been linked with attenuation of age-related diseases, including the risk of bone fractures. In this study, we test the hypothesis that these treatments improve fracture resistance in a mouse model representative of the AD condition. METHODS: Three-month-old male 3xTg-AD mice were treated for 4 months with resveratrol or exercise or both combined, and compared with wild type mice. Exercise training was performed on a treadmill at 15 m/min for 45 min/day, 5 days/week. Resveratrol was given at 4 g/kg diet in the form of pellets. Three-point bending, cross-sectional geometric, and fluorescence analyses were conducted on tibias and compared by treatment group. RESULTS: Tibias of 3xTg mice exhibited signs of diminished bone quality and fracture under less force than age-matched wild type mice (P < 0.05). Treatment with both resveratrol and exercise improved indicators of fracture resistance and bone quality in AD mice to levels comparable to that of wild type mice (P < 0.05). CONCLUSIONS: The 3xTg mouse model of AD is at elevated risk for limb bone fracture compared to wild type controls. Treatment with resveratrol, exercise, or both in combination improves fracture resistance and cross-sectional geometric indicators of bone strength.

Student perception on the integration of simulation experiences into human physiology curricula.

A variety of medical simulators have been developed over recent years for students of all medical professions. These simulators serve to teach basic science concepts, advanced clinical skills, as well as empathy and student confidence. This study aimed to understand the students' perception of the integration of high-fidelity simulation exercises into the teaching of human physiology. Research groups were made up of both osteopathic and podiatric medical students. Data were obtained using a Likert-scale survey. Results indicated that students believed the simulation experiences were beneficial to further understanding of physiological concepts, as well as seeing these concepts in a clinical setting. Variations were noted between podiatric and osteopathic medical students' perception on how the experiences helped them develop clinical and personal confidence, and if the experience helped illustrate correlations between laboratory values and accompanying physiology. Results illustrated no differences in perception between the sexes. Although all students agreed that the experience helped with the understanding of physiology, podiatric medical students did not necessarily find value in the simulation for their development as future clinicians. We predict that differences in perception are largely based on the different curriculums of the students questioned. The present study indicated that incorporation of simulation experiences in the first year of medical school enhanced learning basic science physiology concepts and promoted the development of self-confidence as future clinicians. Incorporating simulation into the didactic coursework should be promoted in other medical schools' curricula.

Optical clearing of small intestine for three-dimensional visualization of cellular proliferation within crypts.

New methods on optical clearing provide a valuable alternative to traditional physical section histology. Optical clearing allows investigation of relatively large tissue samples at histological resolution while maintaining the three-dimensional architecture of the intact system. There is significant potential for applying optical clearing to gastrointestinal tissues. In particular, intestinal crypts contain high concentrations of stem cells, making these structures especially important for research on cellular proliferation in the intestinal epithelium. The objective of our study is to demonstrate an optical clearing method that is easy to implement and is compatible with mitotic fluorescent labeling. The optical clearing method we present utilizes a Triton/DMSO delipidization step followed by refractive index matching, rendering the tissue nearly transparent. We use EdU click chemistry to fluorescently label mitotic cell nuclei. Our results demonstrate successful clearing of jejunal samples with readily visible EdU staining by means of confocal microscopy. Three-dimensional reconstruction of labeled samples reveals preservation of intestinal cytoarchitecture including muscular, submucosal, and mucosal layers. Additionally, the morphology of intestinal crypts and individual EdU-positive mitotic nuclei are visible in sharp detail within their intact three-dimensional organization. In summary, we present an optical clearing method that is easy to implement and has the potential to provide more accurate assessment of cellular proliferation within the gastrointestinal tract in both healthy and disease states.

Genistein treatment improves fracture resistance in obese diabetic mice.

BACKGROUND: Obese, type two diabetics are at an increased risk for fracturing their limb bones in comparison to the general population. Phytoestrogens like as the soy isoflavone genistein have been shown to protect against bone loss. In this study, we tested the effects of genistein treatment on femurs of ob/ob mice, a model for obesity and type two diabetes mellitus. METHODS: Twenty six-week-old female mice were divided into obese (ob/ob) control, obese genistein-treated, lean (ob/+) control, and lean genistein-treated groups (n = 5 each). Treatment with genistein consisted of 600 mg genistein/kg diet. Control mice were given standard rodent chow. At the end of a four-week treatment period, bone histomorphometric and three-point bending properties were compared among groups. RESULTS: Obese mice had larger bone areas (B.Ar.; P < 0.05) and total areas (Tt.Ar.; P < 0.05), but similar bone volume (B.Ar./Tt.Ar.; P > 0.05) of the proximal femoral epiphysis in comparison to lean mice. Treatment with genistein decreased Tt.Ar. and femur length, and increased ultimate force required to fracture the femur and the maximum deformation to failure (P < 0.05). CONCLUSIONS: Genistein improves resistance to fracture from bending loads.

Dietary Genistein Rescues Reduced Basal Chloride Secretion in Diabetic Jejunum via Sex-Dependent Mechanisms.

BACKGROUND/AIMS: The goal of this study was to determine the effect of dietary genistein (naturally occurring phytoestrogen) on jejunal secretory function in a clinically relevant model of diabetes and obesity, the leptin-defIcient ob/ob mouse. METHODS: We measured transepithelial short circuit current (Isc), across freshly isolated segments of jejunum from 12-week old male and female ob/ob and lean C57Bl/6J mice fed a genistein diet (600 mg genistein/kg diet) for 4-weeks. Separate segments of jejunum were frozen for western blot determination of key proteins involved in secretory transport. RESULTS: Basal Isc was signifIcantly decreased (by 33%, P<0.05) in ob/ob females versus leans, and genistein-diet reversed this. Similarly, in males, basal Isc was decreased (by 47%, P<0.05) in ob/ob mice versus leans, and genistein-diet reversed this. Inhibition with either clotrimazole (100 µM, bilateral) or ouabain (100 µM, basolateral) was signifIcantly reduced in ob/ob mice compared to leans (P<0.05), and genistein-diet reversed clotrimazole-sensitive inhibition in ob/ob females, and reversed the ouabain-sensitive inhibition in males (indicating sex-dependent mechanisms). Our data suggested that PDE3 levels were dysregulated in ob/ob females and genistein reversed this. Expression of total CFTR (normalized to actin) was signifIcantly decreased ∼80% (P<0.05) in all ob/ob mice compared to leans, and genistein-diet was without effect. Expression of total NKCC1 (normalized to actin) was signifIcantly decreased ∼80% (P<0.05) in ob/ob male mice versus leans, and genistein-diet reversed this. CONCLUSIONS: Our data suggests that the reduced basal jejunal Isc in ob/ob female mice is a consequence of reduced CFTR expression, decreased activities of the basolateral KCa channel and Na+/K+-ATPase, and in male mice reduced basal jejunal Isc is a consequence of reduced CFTR and NKCC1 expression, along with decreased activities of the basolateral KCa channel and Na+/K+-ATPase. Genistein-diet has beneficial effects on basal Isc mediated by sex-dependent mechanisms in diabetic mice: in females via increased KCa-sensitive Isc and in males via increased Na+/K+-ATPase activity and increased NKCC1 expression. Improved understanding of intestinal dysfunctions in the ob/ob jejunum, may allow for the development of novel drug targets to treat obesity and diabetes, and may also be of benefit in CF-related diabetes.

Resveratrol prevents pulmonary trunk remodeling but not right ventricular hypertrophy in monocrotaline-induced pulmonary hypertension.

Pulmonary hypertension (PAH) is characterized by abnormal vascular remodeling and increased pulmonary artery pressure which lead to right ventricular (RV) hypertrophy and heart failure. Resveratrol (3,5,4'-trihydroxy-trans-stilbene), a dietary polyphenol found in the skins and seeds of grapes, has been found to have antioxidant, anti-proliferative and anti-fibrotic effects. This study examined the effects of resveratrol on cardiac and pulmonary trunk remodeling, and common plasma markers of vascular function in rats with PAH was induced in male Sprague-Dawley rats by a single subcutaneous injection of monocrotaline (MCT, 60mg/kg). Rats were treated with resveratrol (25mg/kg/day) by oral gavage daily for 21days. PAH was confirmed by the presence of increased RV/LV+septum weight, RV and lung weight. In MCT rats, total heart surface area and RV lumen area were increased without corresponding increases in total muscle area, indicating a dilation of the lumen. Pulmonary truck lumen area and thickness of the tunica media were increased by 43% and 44%, respectively, by MCT. Resveratrol had no significant effect on remodeling, although decreases of 12% and 27% were observed for overall heart area and pulmonary truck area, respectively. However, resveratrol significantly reduced the thickness of the pulmonary trunk tunica media. Plasma levels of angiotensin II, aldosterone, C-reactive protein and endothelin-1 were not altered with resveratrol. Our results indicate that daily treatment with resveratrol does not inhibit the abnormal remodeling of the RV induced by MCT, but attenuates the development of medial hypertrophy in the pulmonary trunk.

Genistein stimulates jejunum chloride secretion via an Akt-mediated pathway in intact female mice.

BACKGROUND/AIMS: We have previously shown that daily subcutaneous injections with the naturally occurring phytoestrogen genistein (600 mg genistein/kg body weight/day, 600G) results in a significantly increased basal intestinal chloride, Cl(-), secretion (Isc, a measure of transepithelial secretion) in intact C57BL/6J female mice after 1-week of treatment, compared to controls (DMSO vehicle injected). Removal of endogenous estrogen via ovariectomy (OVX) had no effect on the 600G-mediated increase in basal Isc. METHODS: Given the estrogen-like characteristics of genistein, we compared the effects of daily estradiol (E2) injections (10 mg E2/kg body weight/day, 10E2) on basal Isc in intact and OVX mice. In intact mice, 10E2 was without effect on basal Isc, however, in OVX mice, 10E2 significantly increased basal Isc (mimicked 600G). The goal of the current study was to characterize the intracellular signaling pathways responsible for mediating 600G- or 10E2-stimulated increases in basal Isc in intact female or OVX mice. RESULTS: We measured total protein expression in isolated segments of jejunum using western blot from the following six groups of mice; intact or OVX with; 600G, 10E2 or control. The proteins of interest were: Akt, p-Akt, p-PDK1, p-PTEN, p-c-Raf, p-GSK-3ß, rap-1 and ERK1/2. All blots were normalized to GAPDH levels (n = 6-18/group). CONCLUSION: These data suggest that the presence of the endogenous sex steroid, estrogen, modifies the intracellular signaling pathway required to mediate Cl(-) secretion when the intestine is exposed to exogenous 600G or E2. These studies may have relevance for designing pharmacological tools for women with intestinal chloride secretory dysfunctions.

Ex Vivo Immune Function and Modulatory Effects of Calcitriol in Dogs with Naturally Occurring Diabetes Mellitus.

Human patients with type 1 diabetes mellitus (T1DM) are susceptible to several long-term complications that are related to glycemic control and immune dysregulation. Immune function remains relatively unexplored in dogs with naturally occurring diabetes mellitus (NODM). Calcitriol improves various aspects of immune function in a variety of species, but its effect in diabetic dogs remains unexplored. Therefore, the objectives of this study were to (i) evaluate immune function in dogs with NODM and determine if differences exist based on the level of clinical control and (ii) assess the immunomodulatory effects of calcitriol. Twenty diabetic dogs (clinically controlled, n = ten, not controlled, n = ten) and 20 non-diabetic, healthy control dogs were included in this prospective, case-control study. Whole blood was incubated with calcitriol (10-7 M) or negative control, after which the samples were divided for phagocytosis and leukocyte cytokine response experiments. The phagocytosis of opsonized Escherichia coli (E. coli) was evaluated with flow cytometry. The samples for leukocyte cytokine response evaluations were stimulated with lipopolysaccharide (LPS), lipoteichoic acid (LTA), or phosphate buffer solution (PBS; negative control), and tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-8, and IL-10 were measured in supernatant using a canine-specific multiplex bead-based assay. The leukocytes from diabetic dogs produced higher concentrations of IL-10 (p = 0.01), IL-6 (p < 0.0001), and IL-8 (p < 0.0001) than the control dogs while controlling for the intervention and stimulant. Calcitriol decreased the supernatant concentrations of TNF-α (p < 0.001) and IL-8 (p = 0.04) with concomitant increases in IL-6 (p = 0.005). Diabetic dogs had a lower percentage of leukocytes undergoing phagocytosis (p < 0.0001) but a higher number of bacteria phagocytized per cell (p = 0.001) when compared to the control dogs. Calcitriol had no effect on phagocytic capacity. Lastly, the status of clinical control in diabetic dogs did not yield differences in immune function. These results support that dogs with NODM exhibit immune dysregulation and warrant additional investigation.

Moderate-Intensity Exercise Enhances Mitochondrial Biogenesis Markers in the Skeletal Muscle of a Mouse Model Affected by Diet-Induced Obesity.

Skeletal muscle is composed of bundles of muscle fibers with distinctive characteristics. Oxidative muscle fiber types contain higher mitochondrial content, relying primarily on oxidative phosphorylation for ATP generation. Notably, as a result of obesity, or following prolonged exposure to a high-fat diet, skeletal muscle undergoes a shift in fiber type toward a glycolytic type. Mitochondria are highly dynamic organelles, constantly undergoing mitochondrial biogenesis and dynamic processes. Our study aims to explore the impact of obesity on skeletal muscle mitochondrial biogenesis and dynamics and also ascertain whether the skeletal muscle fiber type shift occurs from the aberrant mitochondrial machinery. Furthermore, we investigated the impact of exercise in preserving the oxidative muscle fiber types despite obesity. Mice were subjected to a normal standard chow and water or high-fat diet with sugar water (HFS) with or without exercise training. After 12 weeks of treatment, the HFS diet resulted in a noteworthy reduction in the markers of mitochondrial content, which was recovered by exercise training. Furthermore, higher mitochondrial biogenesis markers were observed in the exercised group with a subsequent increase in the mitochondrial fission marker. In conclusion, these findings imply a beneficial impact of moderate-intensity exercise on the preservation of oxidative capacity in the muscle of obese mouse models.

The assessment of point-of-care-ultrasound (POCUS) in acute care settings is benefitted by early medical school integration and fellowship training.

CONTEXT: Point-of-care ultrasound (POCUS) has widespread utilization in multiple clinical settings. It has been shown to positively influence clinician confidence in diagnosis and can help appropriately manage patients in acute care settings. There has been a growing trend of increased emphasis on incorporating POCUS training in the first 2 years of the medical school curriculum. OBJECTIVES: This article aims to analyze the clinical use of POCUS in acute settings and how training early in medical school may strengthen clinician confidence and utilization. METHODS: An anonymous 10-question survey on POCUS use was conducted via a secure online platform and distributed to board-certified practicing physicians (MDs and DOs) with educational agreements with Midwestern University (MWU) across acute care specialties. This included preceptors within the MWU graduate medical education clinical consortium. Survey questions were aimed at assessing frequency of use, machine type, reasons for utilizing POCUS, initial ultrasound training, confidence in performing/interpreting POCUS, and perceived impact on patient outcomes. Surveys less than 50% complete were excluded. All surveys returned were more than 50% complete and thus included in the study. Statistical analyses were conducted utilizing the statistical software R version 4.0. RESULTS: Surveys were sent out to 187 participants with 68 responses (36.4% response rate). The survey results demonstrated a relationship between learning POCUS earlier in one's medical career (medical school, residency, or fellowship) to increased use in acute settings when compared to learning POCUS during clinical practice. Of the 68 respondents, 65 (95.6%) indicated that they agree or strongly agree that POCUS use improves patient care, and 64 (94.1%) indicated that they agree or strongly agree that the use of POCUS can improve patient outcomes. CONCLUSIONS: Our survey of acute care physicians indicated that most respondents utilize POCUS daily or weekly (90.8%), and this was related to fewer years of practice (under 10 years from medical school graduation, 94.6%). Moreover, POCUS was utilized primarily in acute care settings for procedures (25%, n=17/68 respondents). These survey results indicate that early integration of POCUS education in osteopathic medical school curricula and throughout fellowship training could likely enhance POCUS utilization in acute care settings.

Genistein Suppresses IL-6 and MMP-13 to Attenuate Osteoarthritis in Obese Diabetic Mice.

Type 2 diabetes mellitus and osteoarthritis (OA) often present as comorbidities. We examined the role of plasma IL-6, chondrocyte MMP-13, and col10a expression in the development of OA in obese diabetic mice. We further investigated dietary genistein and exercise training as potential mitigators of OA. One hundred adult mice (50 females, 50 males) aged 6 weeks were randomized into 5 groups, including lean controls, obese diabetic controls, and obese diabetic mice treated with genistein, exercise training, and genistein plus exercise training. The obese diabetic state was induced by feeding the mice a high-fat, high-sugar diet. Genistein was incorporated into the diet at a concentration of 600 mg genistein/kg. Exercise training was performed on a treadmill and consisted of daily 30 min sessions at 12 m/min, 5 days/week for a 12-week period. After treatment, plasma was collected, and proximal tibias were removed for analysis. Plasma IL-6 and MMP-13 were elevated while col10a was reduced in obese diabetic mice in comparison to lean controls. Dietary genistein treatment reduced IL-6 and MMP-13 expression and increased col10a expression. Histological examination of articular cartilage showed reduced thickness of the uncalcified zones and proteoglycan content in the cartilage of diabetic mice in comparison to mice fed genistein. Exercise training had no significant effect. In conclusion, genistein (and not exercise training) attenuates OA by reducing IL-6 and MMP-13 expression in diabetic mice.

Effects of face masks on oxygen saturation at graded exercise intensities.

CONTEXT: Mask wearing to mitigate the spread of COVID-19 and other viral infections may raise concerns on the effects of face masks on breathing and cardiopulmonary health. Non-evidence-based apprehensions may limit the use of masks in public. OBJECTIVES: We will assess the parameters related to heart and lung physiology between healthy male and female adults exposed to wearing face masks (or not) under conditions of rest and graded exercise. METHODS: We performed a cross-sectional study including 20 male and 20 female adults who met our inclusion criteria. Adults with underlying respiratory and cardiac conditions were excluded. Physiologic parameters were measured while the participants underwent three activity levels (10 min each) in a randomly assigned order: rest, walking, and stair climbing. Each activity level was conducted under three mask conditions: no mask, surgical mask, and N95 respirator. Heart rate (HR) and blood oxygen saturation (SpO2) were recorded via pulse oximeter after each activity. Perceived exertion was recorded utilizing a Borg 15-point scale. A mixed-effects analysis of variance (ANOVA) was utilized to interpret the results. RESULTS: A significant increase in perceived exertion was reported for N95 users (p<0.0001). There was also a significant increase in mean HR for N95 users in comparison to no-mask users (p=0.0031). The mean SpO2 in females was higher than males under rest and walking conditions (p=0.0055). There was no change in SpO2 between mask type overall, nor between mask type vs. exercise intensity, nor between mask type and sex. CONCLUSIONS: Our findings provide evidence that surgical masks and N95 respirators do not influence SpO2 at rest or during exercise.

Genistein stimulates jejunal chloride secretion via sex-dependent, estrogen receptor or adenylate cyclase mechanisms.

BACKGROUND/AIMS: Daily subcutaneous injections with the phytoestrogen genistein, 600 mg/ kg genistein/day (600G) significantly increased intestinal chloride (Cl(-)) secretion (I(sc), µA/cm(2)) in C57BL/6J female and male murine jejunum after 1-2-weeks treatment. METHODS AND RESULTS: In 600G females, basolateral application of the adenylate cyclase inhibitor MDL-12330A (10 µM) significantly reduced basal and total I(sc) in the presence of forskolin (27 and 40% respectively, P < 0.05), with no effect in 600G males, suggesting that 600G-mediated increases in I(sc) in females are due to an adenylate cyclase-dependent mechanism. Concomitant injections with the non-selective estrogen receptor (ER) antagonist ICI-182780 (25 mg/kg/day) resulted in a significant inhibition of basal I(sc) in males (38%, P < 0.05), but was without effect in females (further reinforcing an ER-independent mechanism of action). The ERα-selective antagonist (MPP, 25 mg/kg/day) similarly significantly inhibited the basal I(sc) (37%, P < 0.05) in males, whereas the ERß-selective antagonist (PHTPP, 25 mg/kg/day) was without effect, suggesting that 600G-mediated increases in I (sc) in male mice are due to an ERα-dependent mechanism. Jejunum ERα/actin expression was significantly increased by 600G in males. Compared to intact mice, orchiectomy has differing effects on 600G-mediated basal Isc; castration (CAST) abolished the 600G-mediated increases in I(sc), and ovariectomy (OVX) had no effect on the 600G-stimulated increases in I(sc). Daily estradiol injections (10-20 mg/kg body weight estradiol (10E2 or 20E2) had no effect in intact females, whereas 10E2 significantly increased basal I(sc) in OVX females. CONCLUSION: These data suggest that daily estradiol and genistein injections have differential sex-dependent mechanisms of action on murine intestinal Cl(-) secretion.

Exercise and/or Genistein Do Not Revert 24-Week High-Fat, High-Sugar Diet-Induced Gut Microbiota Diversity Changes in Male C57BL/6J Adult Mice.

The gut microbiota (GM) has been hypothesized to be a potential mediator in the health benefits of exercise and diet. The current literature is focused on the prevention effects of exercise and diet and could benefit from exploring whether these treatments alone or combined can treat obesity via the gut microbiome. This study aimed to explore the effects of genistein, exercise, and their synergistic effect to revert diet-induced obesity and gut microbiota changes. A total of 57 male adult C57BL/6 mice were randomized to 24 weeks of unpurified diet (chow) or a high-fat, high-sugar diet (HFD; 60% fat total energy). After the first 12 weeks, animals on the HFD were randomized into: HFD + chow, HFD, HFD + exercise (HFD + Exe), HFD + genistein (HFD + Gen), and HFD + Exe + Gen. We compared the body weight change between groups after 24 weeks. GM (α-diversity and ß-diversity) was profiled after sequencing the 16S rRNA gene by Illumina MiSeq. HFD + Exe + Gen significantly (p < 0.05) decreased weight gain relative to the HFD with only HFD + chow reverting the body weight change to that of chow. All diets including HFD reduced the GM richness (observed amplicon sequence variants) relative to chow with the HFD + Gen and HFD + Exe resulting in significantly lower phylogenetic diversity compared to the HFD. Data did not support an additive benefit to the GM for HFD + Gen + Exe. HFD + Exe + Gen showed a greater capacity to revert diet-induced obesity in adult male mice, but it was not as effective as switching from HFD to chow. Lifestyle treatment of HFD-induced obesity including exercise and genistein resulted in a reduction in weight gain and GM richness, but switching from HFD to chow had the greatest potential to revert these characteristics toward that of lean controls.

Mitigation of MAFLD in High Fat-High Sucrose-Fructose Fed Mice by a Combination of Genistein Consumption and Exercise Training.

Purpose: Metabolic dysfunction-associated fatty liver disease (MAFLD) is fueled by escalations in both sedentary behavior and caloric intake and is noted in obese type 2 diabetic (T2DM) patients. This study aimed to examine the effects of exercise and the phytoestrogen genistein in mice fed a high fat (60% fat) high sugar (55% fructose with 45% sucrose), HFHS diet. Methods: Male C57BL/6J mice were assigned to five groups: HFHS, HFHS with genistein (600 mg/kg diet, HFHS+Gen), HFHS with moderate exercise (HFHS+Ex), and HFHS with combined genistein and moderate exercise (HFHS-Gen+Ex). Control lean mice were fed standard chow and water. Exercise consisted of 30-minute sessions of treadmill running five days/week for the 12-week study duration. Body weight was assessed weekly. Liver, kidney, fecal pellets and serum were extracted at the end of the study and maintained at -80°C. Results: After 12 weeks of treatment, mice in the HFHS group had the highest hepatic lipid content. Plasma levels of glucose, insulin, leptin, cholesterol, amylin, and total fat content were significantly elevated in HFHS mice compared to control mice. HFHS feeding increased protein expression of carnitine palmitoyltransferase 1b (CPT-1b isoform) in gastrocnemius, CPT1a, glucose transporter protein 2 (GLUT2), glucocorticoid receptor (GR), and fructose 1,6-bisphosphate 1 (FBP1) expression in liver. Exercise alone had minor effects on these metabolic abnormalities. Genistein alone resulted in improvements in body weight, fat content, amylin, insulin sensitivity, and liver histopathology, GR, FBP1, and acetyl-CoA carboxylase 1 (ACC1). Combination treatment resulted in additional metabolic improvements, including reductions in hepatic lipid content and lipid area, alanine transferase activity, CPT1b, and CPT1a. Conclusion: Our results indicate that a HFHS diet is obesogenic, inducing metabolic perturbations consistent with T2DM and MAFLD. Genistein alone and genistein combined with moderate intensity exercise were effective in reducing MAFLD and the aberrations induced by chronic HFHS feeding.

Effects of Genistein and Exercise Training on Brain Damage Induced by a High-Fat High-Sucrose Diet in Female C57BL/6 Mice.

In recent decades, a shift in the nutritional landscape to the Western-style diet has led to an unprecedented rise in the prevalence of obesity and neurodegenerative diseases. Consumption of a healthy diet and engaging in regular physical activity represents safe and affordable approaches known to mitigate the adverse consequences of the Western diet. We examined whether genistein treatment, exercise training, and a combination treatment (genistein and exercise training) mitigated the effects of a Western diet-induced by high-fat, high-sugar (HFHS) in brain of female mice. HFHS increased the amyloid-beta (Aß) load and phosphorylation of tau, apoptosis, and decreased brain-derived neurotrophic factor (BDNF) levels. Exercise training and genistein each afforded modest protection on Aß accumulation and apoptosis, and both increased BDNF. The greatest neuroprotective effect occurred with combination treatment. BDNF and all markers of Aß accumulation, phosphorylation of tau, and apoptosis were improved with combined treatment. In a separate series of experiments, PC12 cells were exposed to high glucose (HG) and palmitate (PA) to determine cell viability with genistein as well as in the presence of tamoxifen, an estrogen receptor antagonist, to assess a mechanism of action of genistein on cell apoptosis. Genistein prevented the neurotoxic effects of HG and PA in PC12 cells and tamoxifen blocked the beneficial effects of genistein on apoptosis. Our results indicate the beneficial effects of genistein and exercise training on HFHS-induced brain damage. The benefits of genistein may occur via estrogen receptor-mediated pathways.