Effects of the aqueous extract of Dicliptera verticillata on fertility and different stages of gestation in female rats

Summary Dicliptera verticillata is a medicinal plant traditionally used in western Cameroon to cure female infertility. This experiment was designed to assess the effects of the aqueous extract of Dicliptera verticillata (AEDv) on fertility and gestation in female rats. Oral increasing doses of AEDv were administered to immature female rats over 20 d. After this time, some animals were mated with fertile males and some fertility parameters were assayed; the other animals were euthanized for preliminary toxicity parameters analysis. The effects of AEDv on the different stages of gestation were assayed on selected animals previously controlled for estrous cycle regularity and mated. AEDv led to an increase in serum, uterine and ovarian proteins as well as in ovarian and uterine weights (P < 0.05) in immature female rats. Hepatic proteins significantly decreased (P < 0.01) in high dose-treated animals (50 and 100 mg/kg) compared with controls. The number of implantation sites and the fertility rate were significantly lower (P < 0.05), while the antifertility activity increased significantly (P < 0.05) in treated rats compared with controls. When administered from the 1st to the 5th day of pregnancy, AEDv led to a decrease of more than 60% in the implantation rate in high dose-treated rats (50, 100, and 400 mg/kg). From the 6th to the 9th day, the implantation, gestation rates and the number of fetuses decreased significantly in all treated groups. From the 11th to the 20th day, a 50% resorption and decrease in gestation rate were reported in 50 mg/kg dose-treated animals. AEDv possesses weak contraceptive and abortifacient effects during pregnancy.

Giantin Is Required for Post-Alcohol Recovery of Golgi in Liver Cells

In hepatocytes and alcohol-metabolizing cultured cells, Golgi undergoes ethanol (EtOH)-induced disorganization. Perinuclear and organized Golgi is important in liver homeostasis, but how the Golgi remains intact is unknown. Work from our laboratories showed that EtOH-altered cellular function could be reversed after alcohol removal; we wanted to determine whether this recovery would apply to Golgi. We used alcohol-metabolizing HepG2 (VA-13) cells (cultured with or without EtOH for 72 h) and rat hepatocytes (control and EtOH-fed (Lieber–DeCarli diet)). For recovery, EtOH was removed and replenished with control medium (48 h for VA-13 cells) or control diet (10 days for rats). Results: EtOH-induced Golgi disassembly was associated with de-dimerization of the largest Golgi matrix protein giantin, along with impaired transport of selected hepatic proteins. After recovery from EtOH, Golgi regained their compact structure, and alterations in giantin and protein transport were restored. In VA-13 cells, when we knocked down giantin, Rab6a GTPase or non-muscle myosin IIB, minimal changes were observed in control conditions, but post-EtOH recovery was impaired. Conclusions: These data provide a link between Golgi organization and plasma membrane protein expression and identify several proteins whose expression is important to maintain Golgi structure during the recovery phase after EtOH administration.

The Role of Golgi Morphology in Post-Alcohol Recovery of Hepatocytes: Observations in Cellular and Animal Models

Background: In hepatocytes and alcohol-metabolizing cultured cells, Golgi undergoes ethanol (EtOH)-induced disorganization. Periniclear and organized Golgi is important in liver homeostasis, but how the Golgi remains intact is unknown. Work from our laboratories showed that EtOH-altered cellular function could be reversed after alcohol removal; we wanted to determine whether this recovery would apply to Golgi. Methods: We used alcohol-metabolizing HepG2 (VA-13) cells (cultured with or without EtOH for 72 h) and rat hepatocytes (control and EtOH-fed (Lieber-DeCarli diet). For recovery, EtOH was removed and replenished with control medium (48 hours for VA-13 cells) or control diet (10 days for rats). Results: EtOH-induced Golgi disassembly was associated with de-dimerization of the largest Golgi matrix protein giantin, along with impaired transport of selected hepatic proteins. After recovery from EtOH, Golgi regained their compact structure, and alterations in giantin and protein transport were restored. In VA-13 cells, when we knocked down giantin, Rab6a GTPase or non-muscle Myosin IIB, minimal changes were observed in control conditions, but post-EtOH recovery was impaired. Conclusions: These data provide a link between Golgi organization and plasma membrane protein expression and identify several proteins whose expression is important to maintain Golgi structure during the recovery phase after EtOH administration.

Diet-induced obesity accelerates blood lactate accumulation of rats in response to incremental exercise to maximum

Blood lactate increases during incremental exercise at high-intensity workloads, and limited exercise capacity is a characteristic of obese animals. This study examined whether blood lactate changes in response to incremental exercise is disrupted in obese animals. Muscular and hepatic proteins that are critical in lactate metabolism were also investigated. Rats were randomized to either standard chow (control) or high-fat diet (HFD) groups. All animals underwent an incremental treadmill test after 14 wk of diet intervention. Blood lactate levels were measured before and after the treadmill test. Activities of mitochondrial oxidative phosphorylation and glycolysis were examined in muscle tissues. Proteins in the liver and skeletal muscles that participate in the turnover of blood lactate were determined by Western blot. Running time in the incremental treadmill test decreased in the HFD group, and blood lactate accumulated faster in these animals than in the control group. Animals with HFD had a decreased level of hepatic monocarboxylate transporter 2, the protein responsible for blood lactate uptake in the liver. Skeletal muscles of animals with HFD showed greater glycolytic activity and decreased content of lactate dehydrogenase B, which converts lactate to pyruvate. We conclude that blood lactate accumulated faster during incremental exercise in obese animals and was associated with their decreased exercise performance. Changes in the metabolic pattern of muscles and changes of liver and muscle proteins associated with lactate utilization likely contribute to the abnormal response of blood lactate to incremental exercise in obese animals.