Sex differences in the impact of body mass index on outcomes of coronary artery disease in Koreans.

BACKGROUND: Obesity is often considered a risk factor for cardiovascular disease, but recent studies have shown conflicting results regarding the effect of BMI on the prognosis of coronary artery disease (CAD). This study aimed to evaluate the relationship between BMI and clinical outcomes of CAD according to sex in a Korean population. METHODS: A total of 3476 patients with a significant CAD who underwent percutaneous coronary intervention (PCI) were enrolled. Patients were classified as follows according to BMI using the Asia-Pacific cutoff points: underweight (<18.5 kg/m 2 ), normal weight (18.5-22.9 kg/m 2 ), overweight (23.0-24.9 kg/m 2 ) and obese (≥25 kg/m 2 ) patients. Underweight and normal weight patients were further categorized into the lower BMI group, whereas overweight and obese patients were categorized into the higher BMI group. The primary endpoint was all-cause mortality. RESULTS: Among women, the higher BMI group showed poor clinical features in the prevalence of hypertension and chest pain presentation, and among men, the higher BMI group had a significantly lower rate of chronic renal failure. At the end of the follow-up period (median 53.5 months), the all-cause mortality rate was lower in the higher BMI group in men, and cardiovascular death and stroke rates were significantly lower in the higher BMI group in women. CONCLUSION: In Korean CAD patients treated with PCI, inverse correlations were observed between the clinical outcomes and BMI, but there were differences between men and women.

HM-chromanone from Portulaca oleracea L. inhibits protein tyrosine phosphatase 1B and mitigates glucose production in insulin-resistant HepG2 cells.

This study aimed to identify the effect of (E)-5-hydroxy-7-methoxy-3-(2'-hydroxybenzyl)-4-chromanone (HM-chromanone), isolated from Portulaca oleracea L., on tyrosine phosphatase 1B (PTP1B) and glucose production in insulin-resistant HepG2 cells. The results revealed that HM-chromanone significantly decreases PTP1B expression and glucose production in insulin-resistant HepG2 cells. Furthermore, a molecular docking stimulation showed HM-chromanone inhibits PTP1B by binding to its active site. Additionally, HM-chromanone was found to significantly modulate insulin receptor substrate-1 (IRS1) by decreasing phosphorylated serine 307 and increasing phosphorylated tyrosine 612 and activating phosphatidylinositol 3-kinase (PI3K) in insulin-resistant HepG2 cells. Furthermore, HM-chromanone augmented the phosphorylation of Akt and forkhead box protein O1 in insulin-resistant HepG2 cells in a dose-dependent manner at the concentrations of 15-60 µM. Additionally, it significantly reduced the expression of glucose 6-phosphatase and phosphoenolpyruvate carboxykinase, which are main enzymes included in hepatic gluconeogenesis. Consequently, HM-chromanone was confirmed to significantly decrease glucose production and increase glucose uptake in insulin-resistant HepG2 cells.

PINK1 deficiency impairs osteoblast differentiation through aberrant mitochondrial homeostasis.

BACKGROUND: PTEN-induced kinase 1 (PINK1) is a serine/threonine-protein kinase in mitochondria that is critical for mitochondrial quality control. PINK1 triggers mitophagy, a selective autophagy of mitochondria, and is involved in mitochondrial regeneration. Although increments of mitochondrial biogenesis and activity are known to be crucial during differentiation, data regarding the specific role of PINK1 in osteogenic maturation and bone remodeling are limited. METHODS: We adopted an ovariectomy model in female wildtype and Pink1-/- mice. Ovariectomized mice were analyzed using micro-CT, H&E staining, Masson's trichrome staining. RT-PCR, western blot, immunofluorescence, alkaline phosphatase, and alizarin red staining were performed to assess the expression of PINK1 and osteogenic markers in silencing of PINK1 MC3T3-E1 cells. Clinical relevance of PINK1 expression levels was determined via qRT-PCR analysis in normal and osteoporosis patients. RESULTS: A significant decrease in bone mass and collagen deposition was observed in the femurs of Pink1-/- mice after ovariectomy. Ex vivo, differentiation of osteoblasts was inhibited upon Pink1 downregulation, accompanied by impaired mitochondrial homeostasis, increased mitochondrial reactive oxygen species production, and defects in mitochondrial calcium handling. Furthermore, PINK1 expression was reduced in bones from patients with osteoporosis, which supports the practical role of PINK1 in human bone disease. CONCLUSIONS: In this study, we demonstrated that activation of PINK1 is a requisite in osteoblasts during differentiation, which is related to mitochondrial quality control and low reactive oxygen species production. Enhancing PINK1 activity might be a possible treatment target in bone diseases as it can promote a healthy pool of functional mitochondria in osteoblasts.