Isoginkgetin, a bioactive constituent from Ginkgo Biloba, protects against obesity-induced cardiomyopathy via enhancing Nrf2/ARE signaling.

Obesity-induced metabolic cardiomyopathy (MC), characterized by lipotoxicity and excessive oxidative stress, emerges as the leading cause of heart failure in the obese patients. Yet, its therapy remains very limited. Here, we demonstrated that isoginkgetin (IGK), a bioactive biflavonoid isolated from medicinal herb Ginkgo Biloba, protected against obesity-induced cardiac diastolic dysfunction and adverse remodeling. Transcriptomics profiling revealed that IGK activated Nrf2 signaling in the heart tissues of the obese mice. Consistent with this observation, IGK treatment increased the nuclear translocation of Nrf2, which in turn trigger the activation of its downstream target genes (e. g. HO-1 and NQO1). In addition, IGK significantly rejuvenated mitochondrial defects in obese heart tissues as evidenced by enhancing mitochondrial respiratory capacity and resisting the collapse of mitochondrial potential and oxidative stress both in vitro and in vivo. Mechanistically, IGK stabilized Nrf2 protein via inhibiting the proteasomal degradation, independent of transcription regulation. Moreover, molecular docking and dynamics simulation assessment demonstrated a good binding mode between IGK and Nrf2/Keap1. Of note, the protective effects conferred by IGK against obesity-induced mitochondrial defects and cardiac dysfunction was compromised by Nrf2 gene silencing both in vitro and in vivo, consolidating a pivotal role of Nrf2 in IGK-elicited myocardial protection against MC. Thus, the present study identifies IGK as a promising drug candidate to alleviate obesity-induced oxidative stress and cardiomyocyte damage through Nrf2 activation, highlighting the therapeutic potential of IGK in ameliorating obesity-induced cardiomyopathy.

Assessing the post-treatment therapeutic effect of tongxie in irritable bowel syndrome: A randomized controlled trial.

Diarrhea predominant irritable bowel syndrome (IBS) is a highly relapsing gastrointestinal disorder decreasing the quality of life. Existing studies indicated that the therapeutic effects maintained for a period of time after the treatments were discontinued (post-treatment therapeutic effects or PTTE). In this study, we aim to assess the PTTE of tongxie. We performed a multiple center, controlled, double blind study of patients with IBS randomized to tongxie (n = 120) or placebo (n = 120) for 4 weeks and followed up for 57 weeks. The primary outcomes were abdominal pains and stool consistency. The secondary outcomes were pain frequency and stool frequency. Tertiary outcomes were adverse effects and global overall symptom. The outcome data were collected at days 1, 2, 3, weeks 1 and 4 during the treatment and at days 1, 2, 3, until week 57 during the post-treatment. Significantly more patients receiving tongxie were clinical responders to the primary and secondary endpoints from day 1 until the end of the treatment. The positive effects of tongxie were maintained until 17-25 weeks after tongxie was discontinued. The relapse-free probabilities in the tongxie group were significantly higher than those in the placebo group (P < .001). Twenty-five weeks after the therapies were discontinued could be considered as IBS natural history. During this period, an average of 53.8-56.3% of patients (pool tongxie and placebo data together) had IBS symptoms (pain scale ≥ 3, stool consistency ≥ 5). In particular, at the end of this study (week 61), 145 (54.2%) patients had IBS symptoms. Our results provide clinical insights into efficient and cost-effective management of refractory IBS, and lend support to the IBS management that the selection of a therapy should consider both its effectiveness during treatment and its PTTE after the treatment.

Effects of diosgenin on myometrial matrix metalloproteinase-2 and -9 activity and expression in ovariectomized rats.

Diosgenin, a traditional Yam extraction, has been used in hormone replacement for menopausal women. We aimed to investigate the influences of diosgenin administration upon the MMP-2 and -9 activity and expression and reproductive hormones of ovariectomized (OVX) rats, a model of menopausal status. Seven-week old female Wistar rats with bilateral OVX or sham operation (controls) were divided and administered different dosages of diosgenin (0, 10, 50, or 100 mg/kg/day) for 8 weeks. Serum was then sampled for progesterone (P4) and estradiol (E2) assay and uterine horns harvested. Myometrial MMP-2 and -9 activity and expression were surveyed and myometrial collagen expression was also assayed. The results show higher body weight in OVX rats across the 8 weeks post surgery and no significant differences were noted among OVX or Sham rats with diosgenin supplements. There were lower P4 and E2 concentrations in OVX rats compared to Sham rats, and higher P4 concentration of Sham rats post diosgenin supplement. MMP-2 and -9 mRNA expression and activity was lower in OVX rats, although higher MMP-2 and lower MMP-9 activity/mRNA expression was observed in OVX rats post diosgenin supplementation. Collagen mRNA expression was higher in OVX rats compared to Sham controls, and diosgenin administration decreased collagen mRNA expression in OVX rats. In conclusion, diosgenin is associated with gelatinase expression and collagen metabolism in OVX rats. Diosgenin administration can partially reverse the effects of OVX upon MMP functions and hormone status. Adequate diosgenin supplement might modulate myometrial gelatinase expression and collagen metabolism in menopausal subjects.