Increased sleep time and reduced energy expenditure contribute to obesity after ovariectomy and a high fat diet

Ojeok-san ameliorates visceral and somatic nociception in a mouse model of colitis induced colorectal cancer

Cancer patients can develop visceral, somatic, and neuropathic pain, largely due to the malignancy itself and its treatments. Often cancer patients and survivors turn to the use of complementary and alternative medicine (CAM) to alleviate pain and fatigue. Thus, it is necessary to investigate how CAM therapies work as novel analgesics to treat cancer pain. Ojeok-san (OJS) is an herbal formula consisting of seventeen herbs. This herbal formula has been shown to possess anti-inflammatory, immunoregulatory, and analgesic properties. In this study, we examined the potential beneficial effects and mechanism of action of OJS in a preclinical model of colitis-associated colorectal cancer. Male and female C57BL/6J mice were exposed to the carcinogen, azoxymethane (AOM, 10 mg/kg) and a chemical inflammatory driver, dextran sulfate sodium (DSS1-2%), to promote tumorigenesis in the colorectum. OJS was given orally (500, 1000, and 2000 mg/kg) to determine its influence on disease activity, tumor burden, nociception, sedation, Erk signaling, and behavioral and metabolic outcomes. In addition, in vitro studies were performed to assess CT-26 cell viability, dorsal root ganglia (DRG) activation, and bone-marrow-derived macrophage (BMDM) inflammatory response to lipopolysaccharide stimulation after OJS treatment. We found that administration of 2000 mg/kg of OJS was able to mitigate mechanical somatic and visceral nociception via Erk signaling without affecting symptom score and polyp number. Moreover, we discovered that OJS has sedative properties and elicits prolonged total sleeping time in AOM/DSS mice. Our in vitro experiments showed that OJS has the capacity to reduce TNFα gene expression in LPS-stimulated BMDM, but no changes were observed in DRG spike number and CT-26 cell proliferation. Taken together, these data suggest that OJS ameliorates nociception in mice and warrants further examination as a potential CAM therapy to promote analgesia.

High Fructose and High Fat Diet Impair Different Types of Memory through Oxidative Stress in a Sex- and Hormone-Dependent Manner

Metabolic syndrome (MetS) contributes to the spread of cardiovascular diseases, diabetes mellitus type 2, and neurodegenerative diseases. Evaluation of sex- and hormone-dependent changes in body weight, blood pressure, blood lipids, oxidative stress markers, and alterations in different types of memory in Sprague–Dawley rats fed with a high fat and high fructose (HFHF) diet were evaluated. After 12 weeks of feeding the male and female rats with HFHF, body weight gain, increase in blood pressure, and generation of dyslipidemia compared to the animals fed with chow diet were observed. Regarding memory, it was noted that gonadectomy reverted the effects of HFHF in the 24 h novel object recognition task and in spatial learning/memory analyzed through Morris water maze, males being more affected than females. Nevertheless, gonadectomy did not revert long-term memory impairment in the passive avoidance task induced by HFHF nor in male or female rats. On the other hand, sex-hormone–diet interaction was observed in the plasma concentration of malondialdehyde and nitric oxide. These results suggest that the changes observed in the memory and learning of MetS animals are sex- and hormone-dependent and correlate to an increase in oxidative stress.

Mineralocorticoid receptor blockade with finerenone improves heart function and exercise capacity in ovariectomized mice

AIMS

In post-menopausal women, incidence of heart failure with preserved ejection fraction is higher than in men. Hormonal replacement therapies did not demonstrate benefits. We tested whether the non-steroidal mineralocorticoid receptor antagonist finerenone limits the progression of heart failure in ovariectomized (OVX) mice with metabolic disorders.

METHODS AND RESULTS

Ovariectomy was performed in 4-month-old mice, treated or not at 7 months old for 1 month with finerenone (Fine) 1 mg/kg/day. Left ventricular (LV) cardiac and coronary endothelial functions were assessed by echocardiography, catheterization, and myography. Blood pressure was measured by plethysmography. Insulin and glucose tolerance tests were performed. Exercise capacity and spontaneous activity were measured on treadmill and in combined indirect calorimetric cages equipped with voluntary running wheel. OVX mice presented LV diastolic dysfunction without modification of ejection fraction compared with controls (CTL), whereas finerenone improved LV filling pressure (LV end-diastolic pressure, mmHg: CTL 3.48 ± 0.41, OVX 6.17 ± 0.30**, OVX + Fine 3.65 ± 0.55† , **P < 0.01 vs. CTL, † P < 0.05 vs. OVX) and compliance (LV end-diastolic pressure-volume relation, mmHg/RVU: CTL 1.65 ± 0.42, OVX 4.77 ± 0.37***, OVX + Fine 2.87 ± 0.26†† , ***P < 0.001 vs. CTL, †† P < 0.01 vs. OVX). Acetylcholine-induced endothelial-dependent relaxation of coronary arteries was impaired in ovariectomized mice and improved by finerenone (relaxation, %: CTL 86 ± 8, OVX 38 ± 3**, OVX + Fine 83 ± 7†† , **P < 0.01 vs. CTL, †† P < 0.01 vs. OVX). Finerenone improved decreased ATP production by subsarcolemmal mitochondria after ovariectomy. Weight gain, increased blood pressure, and decreased insulin and glucose tolerance in OVX mice were improved by finerenone. The exercise capacity at race was diminished in untreated OVX mice only. Spontaneous activity measurements in ovariectomized mice showed decreased horizontal movements, reduced time spent in a running wheel, and reduced VO2 and VCO2 , all parameters improved by finerenone.

CONCLUSIONS

Finerenone improved cardiovascular dysfunction and exercise capacity after ovariectomy-induced LV diastolic dysfunction with preserved ejection fraction.

Obesity induced by estrogen deficiency is associated with hypothalamic inflammation

Occurrence of obesity during the postmenopausal period is closely associated with inflammatory processes in multiple peripheral organs that are metabolically active. Hypothalamic inflammation has been recognized as one of the major underlying causes of various metabolic disorders, including obesity. The association between menopause-related obesity and hypothalamic inflammation remains poorly understood. We observed an elevation in hypothalamic inflammation in the ovariectomized mice, which displayed altered metabolic phenotypes and visceral obesity. Furthermore, we confirmed that ovariectomized mice displayed microglial activation accompanied by the upregulation of multiple genes involved in the inflammatory responses in hypothalamic microglia. Collectively, the current findings suggest that hypothalamic inflammation associated with microglial functioning could be a major pathogenic element in disruption of energy homeostasis during the postmenopausal period.

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Estrogen deficiency induces hypothalamic inflammation.

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Estrogen deficiency leads to inflammatory responses in hypothalamic microglia.

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Hypothalamic inflammation is associated with obesity pathogenesis during the postmenopausal period.