The phosphoinositide 3-kinase p110α is an essential mediator of insulin signaling and glucose homeostasis. We interrogated the human serine, threonine, and tyrosine kinome to search for novel regulators of p110α and found that the Hippo kinases phosphorylate p110α at T1061, which inhibits its activity. This inhibitory state corresponds to a conformational change of a membrane-binding domain on p110α, which impairs its ability to engage membranes. In human primary hepatocytes, cancer cell lines, and rodent tissues, activation of the Hippo kinases MST1/2 using forskolin or epinephrine is associated with phosphorylation of T1061 and inhibition of p110α, impairment of downstream insulin signaling, and suppression of glycolysis and glycogen synthesis. These changes are abrogated when MST1/2 are genetically deleted or inhibited with small molecules or if the T1061 is mutated to alanine. Our study defines an inhibitory pathway of PI3K signaling and a link between epinephrine and insulin signaling.
Hip joint compression can reach up to 3-5 times body weight whilst walking or standing.Femoral neck fractures commonly have a high rate of fixation failure and complications including nonunion and posttraumatic avascular necrosis due to the associated anatomical structures. 1)erefore, in the absence of anatomical reduction and stable implants, the risk of complication rises considerably.The Pauwels classification, which was introduced in 1935, is the first biomechanical classification for femoral neck fractures. 2)This classification calculates the angle between the fracture line of the distal fragment and the horizontal line to determine shearing stress and compressive force. 3)Furthermore, some clinical studies regarding femoral neck fractures have reported that an increased fracture angle is a predictor of postoperative complications.In a vertical orientation femoral neck fracture, the fracture is subjected to greater shear forces rather than
Cachexia is a debilitating comorbidity affecting many lung cancer patients. We have previously found that cachectic mice with lung cancer have reduced serum ketone body levels due to low PPARα activity in the liver. Restoring hepatic PPARα activity with fenofibrate increased circulating ketones and delayed muscle and white adipose tissue wasting. We hypothesized that the loss of circulating ketones plays a pathophysiologic role in cachexia and performed two dietary intervention studies to test this hypothesis. In the first study, male and female mice were randomized to consume either a very low carbohydrate, ketogenic diet (KD) or normal chow (NC) after undergoing tumor induction. The KD successfully restored serum ketone levels and decreased blood glucose in cachectic mice but did not improve body weight maintenance or survival. In fact, there was a trend for the KD to worsen survival in male but not in female mice. In the second study, we compounded a ketone ester supplement into the NC diet (KE) and randomized tumor-bearing mice to KE or NC after tumor induction. We confirmed that KE was able to acutely and chronically increase ketone body abundance in the serum compared to NC. However, the restoration of ketones in the circulation was not able to improve body weight maintenance or survival in male or female mice with lung cancer. Finally, we investigated PPARα activity in the liver of mice fed KE and NC and found that animals fed a ketone ester supplement showed a significant increase in mRNA expression of several PPARα targets. These data negate our initial hypothesis and suggest that restoring ketone body availability in the circulation of mice with lung cancer does not alter cachexia development or improve survival, despite increasing hepatic PPARα activity.
ABSTRACT To develop a vaccine to block the transmission of vivax malaria, the gene encoding the ookinete surface protein Pvs25 was cloned from a Korean malaria patient. The Pvs25 gene was 660 bp long, encoding 219 amino acids. It was subcloned into the expression vector pQE30 and expressed in Escherichia coli . The expressed recombinant protein, named rPvs25, showed a molecular mass of approximately 25 kDa by SDS-PAGE analysis. An anti-rPvs25 monoclonal antibody produced in BALB/c mice was able to inhibit sporozoite development in the mosquito Anopheles sinensis , which is known as the malaria transmission vector in the Republic of Korea. In addition, rPvs25 produced a relatively high antibody titer in BALB/c mice that lasted for more than 6 months. Based on these results, we suggest that recombinant Pvs25 could be a useful antigen in the development of a vaccine to prevent local malaria transmission in the Republic of Korea.
Introduction: The role of neuronal cell specific ROCK2 in ischemic stroke in vivo has been poorly investigated. We investigated the pharmacological effect of selective ROCK2 inhibition by selective ROCK2 inhibitor, KD025 and the genetic effect using neuronal specific ROCK2 knockout (ROCK2Eno2-/-) mice. Methods: Isoflurane-anesthetized littermate control (LC) and ROCK2Eno2-/- mice (20-22 g) underwent ischemia (2h middle cerebral artery occlusion (MCAO)/reperfusion (22h after 2h MCAO) injury model. An 8.0 nylon monofilament coated with a silicone was introduced into the left internal carotid artery up to the anterior cerebral artery. To assess the mechanism of ROCK2 deficiency in neuronal cells, we seeded hippocampal neuronal (HT22) cells in 6-well plates and transfected ROCK2 siRNA. Phosphorylated glycogen synthase kinase 3 beta (pGSK-3β) and Tau proteins which were involved in neuroprotection were measured by western blotting from brain lysates and neuronal cells. Infarction volume was measured by TTC staining and evaluation of behavioral was assessed by neurological deficit score (NDS) at 22h after MCAO. Results: In WT mice, ROCK2 inhibition by KD025 (100 mg/kg, p.o.) decreased infarct volumes and improved the NDS in ischemic stroke. ROCK activity (p-MYPT1 to MYPT1 ratio) of the brain lysates by KD025 was decreased dose-dependently in ischemic mice brain. In genetic modified mice, infarction volume (64.6 ± 10.4 vs. LC (102.3 ± 12.4), n=5) of ROCK2Eno2-/- mice was significantly decreased by 37% and the NDSs (1.8 ± 0.4 vs. LC (2.8 ± 0.5), n=5) were improved by 36% compared to the LC groups. Both pGSK-3β and Tau in HT22 cells with ROCK2 siRNA transfection and ROCK2Eno2-/- mice brain was significantly decreased compared to each respective controls. Conclusion: These findings indicate that neuronal ROCK2 plays important role in ischemic stroke via GSK-3β and Tau signaling pathways and inhibition of neuronal specific ROCK2 may have therapeutic benefits in ischemic stroke.
Saliva is vital to oral health, fulfilling multiple functions in the oral cavity. Three pairs of major salivary glands and hundreds of minor salivary glands collectively secrete the complex fluid, which is produced by two distinct acinar cell populations. Serous acinar cells secrete a watery saliva containing enzymes, while mucous acinar cells secrete a more viscous fluid containing highly glycosylated mucins. Despite their shared developmental origins, the parotid gland (PG) is comprised of only serous acinar cells, while the sublingual gland (SLG) contains predominantly mucous acinar cells. The instructive signals that govern the identity of serous versus mucous acinar cell phenotypes are not yet known. The homeobox transcription factor Nkx2.3 is uniquely expressed in the SLG. When the Nkx2.3 gene was disrupted, the maturation of SLG mucous acinar cells was reported to be delayed. To examine whether Nkx2.3 plays a role in directing the mucous cell phenotype, we analyzed SLG from Nkx2.3-/- mice using RNAseq, immunostaining and proteomic analysis of saliva. Our results indicate that Nkx2.3, most likely in concert with other transcription factors uniquely expressed in the SLG, is a key regulator of the molecular program that specifies the identity of mucous acinar cells.
Introduction: Wistar Han rats are a preferred strain of rodents for general toxicology and safety pharmacology studies in drug development. In some of these studies, visual functional tests that assess for retinal toxicity are included as an additional endpoint. Although the influence of gender on human retinal function has been documented for more than 6 decades, preclinically it is still uncertain if there are differences in retinal function between naïve male and female Wistar Han rats. Methods: In this study, sex-related differences in the retinal function were quantified by analyzing electroretinography (ERG) in 7-9-week-old (n = 52 males and 51 females) and 21-23-week-old Wistar Han rats (n = 48 males and 51 females). Optokinetic tracking response, brainstem auditory evoked potential, ultrasonic vocalization and histology were tested and evaluated in a subset of animals to investigate the potential compensation mechanisms of spontaneous blindness. Results/Discussion: Absence of scotopic and photopic ERG responses was found in 13% of 7-9-week-old (7/52) and 19% of 21-23-week-old males (9/48), but none of female rats (0/51). The averaged amplitudes of rod- and cone-mediated ERG b-wave responses obtained from males were significantly smaller than the amplitudes of the same responses from age-matched females (-43% and -26%, respectively) at 7-9 weeks of age. There was no difference in the retinal and brain morphology, brainstem auditory responses, or ultrasonic vocalizations between the animals with normal and abnormal ERGs at 21-23 weeks of age. In summary, male Wistar Han rats had altered retinal responses, including a complete lack of responses to test flash stimuli (i.e., blindness), when compared with female rats at 7-9 and 21-23 weeks of age. Therefore, sex differences should be considered when using Wistar Han rats in toxicity and safety pharmacology studies with regards to data interpretation of retinal functional assessments.
SUMMARY The phosphoinositide 3-kinase, p110α, is an essential mediator of insulin signaling and glucose homeostasis. We systematically interrogated the human serine, threonine, and tyrosine kinome to search for novel regulators of p110α and found that the Hippo kinases phosphorylate and completely inhibit its activity. This inhibitory state corresponds to a conformational change of a membrane binding domain on p110α, which impairs its ability to engage membranes. In human primary hepatocytes, cancer cell lines, and rodent tissues, activation of the Hippo kinases, MST1/2, using forskolin or epinephrine is associated with phosphorylation and inhibition of p110α, impairment of downstream insulin signaling, and suppression of glycolysis and glycogen synthesis. These changes are abrogated when MST1/2 are genetically deleted or inhibited with small molecules. Our study reveals a novel inhibitory pathway of PI3K signaling and a previously unappreciated link between epinephrine and insulin signaling.
