Clinical Utility of Sperm Function Tests in Predicting Male Fertility: A Systematic Review.

Routine semen analysis provides considerable information regarding sperm parameters; however, it is not solely adequate to predict male fertility potential. In the past two decades, several advance sperm function tests have been developed. The present systematic review intends to assess the clinical utility of available advance sperm function tests in predicting the male fertility potential. A systematic literature search was conducted as per PRISMA guidelines using PubMed, MEDLINE, Google Scholar, and Cochrane Library. Different keywords either singly or in combination were used to retrieve the relevant articles related to sperm function tests, male fertility, and pregnancy outcomes. A total of 5169 articles were obtained, out of which 110 meeting the selection criteria were included in this review. The majorly investigated sperm function tests are hypo-osmotic swelling test, acrosome reaction test, sperm capacitation test, hemizona binding assay, sperm DNA fragmentation test, seminal reactive oxygen species test, mitochondrial dysfunction tests, antisperm antibody test, nuclear chromatin de-condensation (NCD) test, etc. The different advance sperm function tests analyse different aspects of sperm function. Hence, any one test may not be helpful to appropriately predict the male fertility potential. Currently, the unavailability of high-quality clinical data, robust thresholds, complex protocols, high cost, etc., are the limiting factors and prohibiting current sperm function tests to reach the clinics. Further multi-centric research efforts are required to fulfil the existing lacunas and pave the way for these tests to be introduced into the clinics.

Varicocoele-associated male infertility: Cellular and molecular perspectives of pathophysiology.

BACKGROUND: Varicocoele is a common risk factor associated with reduced male fertility potential. The current understanding of varicocoele pathophysiology does not completely explain the clinical manifestation of infertility. The present treatment options such as antioxidant supplementation and varicocoelectomy only help ≈35% of men to achieve spontaneous pregnancy. OBJECTIVE: This review aims to summarize the available knowledge on cellular and molecular alterations implicated to varicocoele-associated male infertility and also highlights the new knowledge generated by "omics" technologies. MATERIALS AND METHODS: PubMed, MEDLINE, Cochrane and Google Scholar databases are searched using different combinations of keywords (varicocoele, infertile/fertile men with varicocoele, cellular changes, molecular mechanisms, proteome, epigenome, transcriptome and metabolome). A total of 229 relevant human and animal studies published till 2021 were included in this review. RESULTS: Current understanding advocates oxidative stress (OS) as a major contributory factor to varicocoele-associated male infertility. Excessive OS causes alteration in testicular microenvironment and sperm DNA fragmentation, which further contributes to infertility. Molecular and omics studies have identified several promising biomarkers such as AAMP, SPINT1, MKI67 (genetic markers), sperm quality and function related protein markers, global sperm DNA methylation level (epigenetic marker), Hspa2, Protamine, Gadd7, Dynlt1 and Beclin1 (mRNA markers), PRDX2, HSPA, APOA2, YKL40 (seminal protein markers), total choline and PHGDH (metabolic markers). DISCUSSION: Mature spermatozoa harbours a plethora of molecular information in form of proteome, epigenome and transcriptome, which could provide very important clues regarding pathophysiology of varicocoele-associated infertility. Recent molecular and omics studies in infertile men with varicocoele have identified several promising biomarkers. Upon further validation with larger and well-defined studies, some of these biomarkers could aid in varicocoele management. CONCLUSION: The present evidences suggest that inclusion of OS and sperm DNA fragmentation tests could be useful to the diagnostic workup for men with varicocoele. Furthermore, including precise molecular markers may assist in diagnostics and prognostics of varicocoele-associated male infertility.

Traditional Dietary Knowledge of a Marginal Hill Community in the Central Himalaya: Implications for Food, Nutrition, and Medicinal Security.

Himalayan communities illustrate a rich agriculture-medicine use system that not only provides adequate dietary diversity and nutrition but also delivers therapeutic security. This study explores the food-medicine interface as observed by the marginal hill communities in the central Himalaya with an aim to assess traditional agriculture and food plants with relation to dietary diversity and nutritional and medicinal values based on comprehensive research. A total of 445 respondents were interviewed to obtain data on food intakes using dietary recall methods and dietary diversity indices (DDIs). The ethnomedical use of plant species was gathered from respondents as well as from various published studies for respective species. Nutritional parameters were collected from the Indian Food Composition Table developed by the ICMR, India to analyze the average nutritional intake. The traditional food system achieves the dietary and nutritional needs of the community within the standard norms. The average household dietary diversity of 7.45, 7.34, and 8.39 in summer, monsoon, and winter seasons, respectively, sustain 79, 74, and 93% of energy requirements in respective, seasons. The average food consumption score (FCS) was 73.46, and all the food exhibited rich phytochemicals, such as amino acids, alkaloids, carotenoids, flavonoids, glycosides, and phenolic acids. These plants also provided effective treatments against several ailments and illnesses, such as cardiovascular diseases, diabetics, gastrointestinal issues, and inflammation The indigenous cuisines also have significant food and medicinal values. Considering that the community had significant knowledge of food systems with their nutritional and therapeutic utility, there is a need to protect and document this indigenous knowledge. Also, most of the crops are still under cultivation, so there is a need to create more awareness about the nutritional and therapeutic value of the system so that it could be retained intact and continued. The implications of this research are of both academic importance and practical significance to ensure food-medicine security and avoid malnutrition among rural communities. It is expected that the study would lead to renewed thinking and policy attention on traditional agriculture for its role in food and nutritional security that may lead to a sustainable food supply system.

Decrease in DNA methylation 1 interacts with chromomethylase and like heterochromatin protein 1 in Physcomitrella patens.

The nucleosome remodeling protein decrease in DNA methylation 1 (DDM1)/Lsh maintains normal levels of DNA methylation. Direct interaction between Lsh and DNA methyltransferase 1 (Dnmt1) and their localization to heterochromatin in the presence of heterochromatin protein-1α (HP1α) is a mechanism by which the concentration of DNMTs is increased at heterochromatin, and chromosome structures are stabilized in metazoans. In plants, however, it is unclear how DDM1 cooperates with methyltransferases and like heterochromatin protein 1 (LHP1). In this study, we provide evidence for a novel interaction between moss DDM1 (PpDDM1) and the chromomethylase PpCMT, that has not been reported in any plant, and between PpDDM1 and PpLHP1, that has not been reported before in any organism. Our protein-protein interaction studies may provide mechanistic insight into heterochromatin regulation.

Functional characterization of LIKE HETEROCHROMATIN PROTEIN 1 in the moss Physcomitrella patens: its conserved protein interactions in land plants.

In flowering plants, LIKE HETEROCHROMATIN PROTEIN 1 (LHP1)/TERMINAL FLOWER 2 (TFL2) is known to interact with polycomb group (PcG) and non-PcG proteins and control developmental programs. LHP1/TFL2 is an ancient protein and has been characterized in the early-divergent plant Physcomitrella patens. However, interacting partners of PpLHP1 other than the chromomethylase PpCMT have not been identified to date. Also, while functional polycomb repressive complex 2 (PRC2) is known to exist in P. patens, there is no experimental evidence to support the existence of PRC1-like complexes in these mosses. In this study, using protein-protein interaction methods, transient expression assays and targeted gene knockout strategy, we report the conserved properties of LHP1/TFL2 using the Physcomitrella system. We show that a PRC1-like core complex comprising of PpLHP1 and the putative PRC1 Really Interesting New Gene (RING)-finger proteins can form in vivo. Also, the interaction between PpRING and the PRC2 subunit PpCLF further sheds light on the possible existence of combinatorial interactions between the Polycomb Repressive Complex (PRC) in early land plants. Based on the interaction between PpLHP1 and putative hnRNP PpLIF2-like in planta, we propose that the link between PpLHP1 regulation and RNA metabolic processes was established early in plants. The conserved subnuclear distribution pattern of PpLHP1 in moss protonema further provides insight into the manner in which LHP1/TFL2 are sequestered in the nucleoplasm in discrete foci. The PpLHP1 loss-of-function plants generated in this study share some of the pleiotropic defects with multiple aberrations reported in lhp1/tfl2. Taken together, this work documents an active role for PpLHP1 in epigenetic regulatory network in P. patens.

Physcomitrella patens DNA methyltransferase 2 is required for recovery from salt and osmotic stress.

DNA methyltransferase 2 (DNMT2) unlike other members of the cytosine DNA methyltransferase gene family has dual substrate specificity and it methylates cytosines in both the DNA and transfer RNA (tRNA). Its role in plants, however, has remained obscure to date. In this study, we demonstrate that DNMT2 from Physcomitrella patens accumulates in a temporal manner under salt and osmotic stress showing maximum accumulation during recovery, i.e. 24 h after plants are transferred to normal growth medium. Therefore, to study its role in stress tolerance, we generated PpDNMT2 targeted knockout plants (ppdnmt2ko). Mutant plants show increased sensitivity to salt and osmotic stress and are unable to recover even after 21 days of growth on optimal growth media. ppdnmt2ko, however, accumulate normal levels of dehydrin-like and small heat shock protein encoding transcripts under stress but show dramatic reduction in levels of tRNA(A) (sp-) (GUC) . The levels of tRNA(A) (sp-) (GUC) , in contrast, increase ~ 25-30-fold in ppdnmt2ko under non-stress conditions and > 1200-fold in wild-type plants under stress. The role of PpDNMT2 in modulating biogenesis/stability of tRNA(A) (sp-) (GUC) under salt and osmotic stress is discussed in the light of these observations.