IMPACT OF AMPK ACTIVATOR METFORMIN ON SPERM QUALITY

Semen cryopreservation allows crucial management of animal genetic diversity. However, the freeze-thaw process causes biochemical and physical alterations, impairing sperm energy-dependent functions. Currently, many chemicals are added to the media to enhance frozen-thawed sperm quality during artificial insemination. The aims of this study was to determine the effects of Metformin (Metf) on fresh chicken sperm motility and ability to perform acrosome reaction, and to evaluate Metf’s effects on the functions of cryopreserved sperm. Chicken semen was diluted and incubated at 35°C in media supplemented with or without different doses of 5’-AMP-Activated Protein Kinase (AMPK) activator, Metf (0,5 to 5 mM). We then looked for the concentration improving the most sperm quality to use it in the cryopreservation media used for chicken sperm. Our results show that 1 mM Metf is the concentration giving the best results regarding sperm quality. AMPKα phosphorylation, viability, acrosome reaction ability (AR), and various motility parameters, were negatively affected by the freeze-thaw process, and that Metf partially restored them. Sperm quality improved (mean increased by 23% for motility, by 10% for viability) as well as AMPKα phosphorylation (mean increased by 30%). Moreover, fluorescent intensity levels of phospho-AMPK were also stronger with Metf than in the control. These results show that the presence of Metf in fresh semen has a positive impact on the quality of sperm and helps reducing the gradual decline in sperm motility caused by cryopreservation by partially restoring several essential sperm functions, and thus leads to a better overall quality of cryopreserved sperm

Effect of fluoxetine on cyclic adenosine monophosphate response to follicle-stimulating hormone in HEK cells

Fluoxetine is an antidepressant that acts as a selective serotonin reuptake inhibitor. Fluoxetine has exhibited different mechanisms of action on many different cell lines. In this study, the effect of fluoxetine on cAMP production in human embryonic kidney (HEK) cells under the stimulation of bovine follicle-stimulating hormone were examined. HEK cells were incubated for 60 minutes with fluoxetine at different concentrations (0, 6.25, 12.5, 25 and 50 μM), and then cAMP accumulation, ATP level, and AMPK phosphorylation and cell viability were tested. Our results showed that fluoxetine at 25 and 50 μM attenuated cAMP levels in cells after bFSH stimulation. The depletion of cAMP at this concentration is accompanied by a decrease in ATP energy and an increased capacity to phosphorylate AMPK. As such, this study showed that fluoxetine induces a reduction in cAMP accumulation and that it is associated with the AMPK pathway in HEK cell

Vector abundance and species composition of Anopheles mosquitoin Central Region and Central West Highlands, Viet Nam

Malaria is a major cause of morbidity and mortality in Viet Nam. In 2008, World Health Organization reported an estimated value of 243 million cases with a mortality of about 863 thousand in the world. Malaria transmission in the Central Region and Central West Highlands of Viet Nam is known to be holoendemic and perennial. High humidity (80%) and a high mean temperature of 25°C in this area favour the bionomics of the principal malaria vectors. Vector control is a major component of the Global Malaria Control Strategy and still remains the most generally effective measure to prevent malaria transmission. Successful application of vector control measures requires the understanding of the bionomics of Anopheles species responsible for malaria transmission, including correct and precise identification of the target species and its distribution.This study was conducted to provide information on the vector abundance and species composition of Anopheles mosquito at Quang Binh, Binh Đinh, Khanh Hoa, Ninh Thuan, Gia Lai, Dak Lak ofCentral Region and Central West Highlands of Viet Nam. A total of 18 Anopheles species were collected in these provinces, therein, the 2main vectors are An. minimus and An. dirus, and the 3 secondary vectors are An. aconitus, An. jeyporiensis, An. maculatus. An. dirus and An. minimus species are present in most of the studied communes in 6 provinces, An. aconitus, An. jeyporiensis and An. maculatusare present in Binh Dinh, Ninh Thuan and Gia Lai provinces, whileAn. jeyporiensisdoes not seem to be found in the other provinces

THÀNH PHẦN LOÀI LƯỠNG CƯ (AMPHIBIA) VÀ BÒ SÁT (REPTILIA) Ở HUYỆN ĐỨC CƠ, TỈNH GIA LAI

As a result of our field work caried out in 2020 and 2021, we herein report the first herpetofaunal list of Duc Co dictrict, Gia Lai province, comprising 21 species of amphibians (14 genera, six families, two orders) and 40 species of reptiles (35 genera, 16 families, 2 orders). Remarkably, nine species are recored for the fist time in Gia Lai province, namely Kalophrynus interlineatus, Limnonectes dabanus, Dixonius minhlei, Lygosoma bowringii, Dendrelaphis subocularis, Lycodon subcinctus, Heosemys grandis, Siebenrockiella crassicollis, and Indotestudo elongata. In terms of conservation concern, 10 species are listed the Vietnam Red Data Book (2007) and 10 species in the IUCN Red List (2021).Nghiên cứu tiến hành trong hai năm 2020–2021 tại huyện Đức Cơ, tỉnh Gia Lai, đã ghi nhận 21 loài lưỡng cư thuộc 14 giống, 6 họ, 2 bộ và 40 loài bò sát thuộc 35 giống, 16 họ, 2 bộ. Đáng chú ý, kết quả nghiên cứu đã bổ sung 9 loài cho khu hệ lưỡng cư, bò sát (LCBS) của tỉnh Gia Lai bao gồm: Kalophrynus interlineatus, Limnonectes dabanus, Dixonius minhlei, Lygosoma bowringii, Dendrelaphis subocularis, Lycodon subcinctus, Heosemys grandis, Siebenrockiella crassicollis và Indotestudo elongata. Trong đó, 14 loài bị đe dọa cần được ưu tiên bảo tồn gồm 10 loài có tên trong Sách Đỏ Việt Nam (2007) và 10 loài có tên trong Danh lục Đỏ IUCN (2021)

Circulating Biomarkers for Early Diagnosis of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors, which is also often fatal. An early and accurate diagnosis is a decisive step towards the survival of the patients. Molecular biology improved significantly the prognosis of liver cancers through learned use of tumor markers like proteantigens, cytokines, enzymes, isoenzymes, circulating RNAs, gene mutations and methylations. Nevertheless, much improvement is still achievable and needed in this area, which is crucial in order to make an early diagnosis and monitor the progression of the disease. We present in this review what we believe to be the most relevant data regarding tissue and serum biomarkers related to HCC

Natural and recombinant equine chorionic gonadotropins past and future in animal reproductive technology

Equine Chorionic Gonadotropin (eCG) previously named Pregnant Mare Serum Gonadotropin (PMSG) has been widely used since the 40s in animal reproduction control. It is extracted from the blood of pregnant mares between days 40 and 120 of gestation. Animal welfare organizations have voiced concerns against mares bleeding conditions. There is currently no effective substitute for the natural PMSG. In this review, we summarize the basic knowledge of the structure and biology of eCG, and the research on recombinant eCG production in the past five years

A Multi-Center Randomized Trial to Assess the Efficacy of Gatifloxacin versus Ciprofloxacin for the Treatment of Shigellosis in Vietnamese Children

The bacterial genus Shigella is the most common cause of dysentery (diarrhea containing blood and/or mucus) and the disease is common in developing countries with limitations in sanitation. Children are most at risk of infection and frequently require hospitalization and antimicrobial therapy. The WHO currently recommends the fluoroquinolone, ciprofloxacin, for the treatment of childhood Shigella infections. In recent years there has been a sharp increase in the number of organisms that exhibit resistance to nalidixic acid (an antimicrobial related to ciprofloxacin), corresponding with reduced susceptibility to ciprofloxacin. We hypothesized that infections with Shigella strains that demonstrate resistance to nalidixic acid may prevent effective treatment with ciprofloxacin. We performed a randomized controlled trial to compare 3 day ciprofloxacin therapy with 3 days of gatifloxacin, a newer generation fluoroquinolone with greater activity than ciprofloxacin. We measured treatment failure and time to the cessation of individual disease symptoms in 249 children with dysentery treated with gatifloxacin and 245 treated with ciprofloxacin. We could identify no significant differences in treatment failure between the two groups or in time to the cessation of individual symptoms. We conclude that, in Vietnam, ciprofloxacin and gatifloxacin are similarly effective for the treatment of acute dysentery

Role of signaling key proteins in the quality of reproduction cells destined to be cryopreserved

L'AMPK est un senseur cellulaire des réserves énergétiques de l’organisme. Les spermatozoïdes, mobilisent beaucoup d’énergie pour leur mobilité et la fécondation de l’ovocyte. L’objectif de ce travail était de caractériser et décrire des éléments clés de la voie de signalisation de l'AMPK, de comprendre leur implication dans les spermatozoïdes de coq et d’étudier comment leurs modulateurs peuvent impacter les fonctions des gamètes conservés in vitro. Nous avons montré une augmentation de la mobilité et de la réaction acrosomique dans les spermatozoïdes exposés à l'AICAR et à la metformine, des activateur de l’AMPK, y compris après avoir été congelés. Ces activateurs ont partiellement restauré les activités des enzymes antioxydantes (SOD, GPx, GR): et diminué les ROS et la LPO dans les spermatozoïdes décongelés. Nous avons établi la présence des CaMKKs (α et β) et de CaMKI dans les spermatozoïdes et leur rôle lié au calcium extracellulaire (via les canaux calcique SOCs) dans la voie de régulation de l'AMPK et dans la mobilité et la réaction acrosomique des spermatozoïdes. En conclusion, ce travail confirme le rôle de différents acteurs de signalisation liés au métabolisme énergétique et aux flux calciques dans les fonctions des spermatozoïdes.AMPK is a cellular sensor of body energy reserves. Spermatozoa mobilize a lot of energy for their motility and the fertilization of the oocyte. The objective of this work was to characterize and describe key elements of the signaling pathway of AMPK, understand their involvement in chicken spermatozoa and study how their modulators may impact the functions of in vitro preserved gametes. We showed an increase in mobility and acrosome reaction in spermatozoa exposed to AICAR and metformin, activators of AMPK, including after freezing. These activators have partially restored the activities of antioxidant enzymes (SOD, GPx, GR): and decreased ROS and LPO in thawed spermatozoa. We have established the presence of CaMKKs (α and β) and CaMKI in sperm and their role related to extracellular calcium (via calcium channels SOCs) in the control channel of AMPK and in motility and acrosome reaction of spermatozoa. In conclusion, this work confirms the role of different signaling actors related to energy metabolism and calcium fluxes in spermatozoa functions

Roles of Soluble Adenylyl Cyclase in cAMP Synthesis in Animal Cells

The second messenger cyclic adenosine 3′,5′-monophosphate (cAMP) synthesis is catalyzed by adenylyl cyclases (ACs). The second messenger cAMP participates in many physiological processes in cells. All eukaryotic adenylyl cyclases (transmembrane adenylyl cyclase and soluble adenylyl cyclases) belong to class III. Soluble adenylyl cyclase was identified in many studies as a widely expressed intracellular source of cAMP in mammalian and non-mammalian cells. Soluble adenylyl cyclase is evolutionary, structurally, and biochemically distinct from the G-protein-responsive transmembrane adenylyl cyclase. sAC is distributed throughout the cytoplasm and it may be present in the nucleus and in mitochondria. sAC has been confirmed to be a bicarbonate sensor in a variety of mammalian cell types. Here I review the physiological role of soluble adenylyl cyclase in different mammalian and non-mammalian tissues. These data promote further research to clarify the exact roles of soluble adenylyl cyclase in the development of the biological activity of normal cells in the body and the therapeutic implications.