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Scientific Rationale for the Use of Single Herb Remedies in Ayurveda
Published in D. Suresh Kumar, Ayurveda in the New Millennium, 2020
S. Ajayan, R. Ajith Kumar, Nirmal Narayanan
A major characteristic of defective human spermatozoa is the presence of large amounts of DNA damage, which is largely oxidative and is closely associated with defects in spermiogenesis. Spermiogenesis is disrupted by oxidative stress, leading to the production of defective gametes with poorly remodeled chromatin that are particularly susceptible to free radical attack. To worsen the situation, these defective cells have a tendency to undergo an unusual form of apoptosis associated with high amounts of superoxide generation by the sperm mitochondria. This leads to significant oxidative DNA damage that eventually culminates in the DNA fragmentation found in infertile patients (Aitken and Curry 2011). Studies have shown that the tuberous root of I. digitata possesses considerable antioxidant activity (Alagumanivasagam et al. 2010,2011). It is plausible that the free radical scavenging activity of I. digitata may be responsible for its aphrodisiac properties.
Mammalian Spermatozoa
Published in Claude Gagnon, Controls of Sperm Motility, 2020
Mammalian spermiogenesis is a remarkably slow process as it was disclosed by the use of the radioactive tracer 3H-thymidine and the technique of radioautography. Indeed, spermiogenesis lasts approximately 20 days in the rat;152,153 15 days in the mouse, hamster, and monkey;154,155 and 23 days in man,156 and the exact duration of each phase and step of spermiogenesis was also estimated in these studies.
Influence of Environmental Agents on Male Reproductive Failure
Published in Vilma R. Hunt, Kathleen Lucas-Wallace, Jeanne M. Manson, Work and the Health of Women, 2020
The process of spermiogenesis consists of three developmental processes: acrosome formation, nuclear condensation, and tail formation. Spermatids lose most of their cytoplasm and undergo remarkable transformation into spermatozoa without cell division. During spermiogenesis, cytoplasm containing Golgi bodies, vesicles, degenerating mitochondria, lipid droplets, and ribosomes is extruded from the germinal cell and phagocytized by Sertoli cells.81
Mapping the human sperm proteome – novel insights into reproductive research
Published in Expert Review of Proteomics, 2023
Mika Alexia Miyazaki, Raquel Lozano Guilharducci, Paula Intasqui, Ricardo Pimenta Bertolla
In fact, there are only two studies published about the hormones and xenohormones influence in sperm proteome. Grande and coworkers identified 42 DEPs in men with testosterone deficiency (i.e. male hypogonadism). Among these, 18% were correlated with human reproduction, and, of these, 37% were linked to sperm motility and capacitation, 42% with fertilization and oocyte interaction and 21% with spermatogenesis. Noteworthy, underexpression of Hydrocephalus-inducing protein homolog (HYDIN), ROPN1B, AKAP3, and AKAP4 was related to the impairment in sperm motility observed in these men [68], which is in line with other studies cited in the semen quality section [55,62,70]. Moreover, the dysfunction in Leydig Cells is one of the main the reasons for the infertility of hypogonadic patients, since proteins involved in spermiogenesis, such as mitochondrial carrier homolog 1 (PSAP), ROPN1B, SERPINA5, and SPARC-related modular calcium-binding protein 1 (SMOC1), were also found among the DEPs [68].
The effect of melatonin on testis histological changes and spermatogenesis indexes in mice following treatment with dexamethasone
Published in Drug and Chemical Toxicology, 2022
Malek Soleimani Mehranjani, Mina Azizi, Firouzeh Sadeghzadeh
100 round seminiferous tubule cross-sections in each testis tissue were randomly selected under a light microscope. All spermatogenic and Sertoli cells were counted and spermatogenesis indexes including tubule differentiation index (TDI), Spermiogenesis index (SPI), meiotic index (MI) and Sertoli cell index (SCI) were calculated. The tubule differentiation index (TDI) is defined as the percentage of seminiferous tubules containing at least three differentiated germ cells (spermatocyte, round and long spermatid) from the B spermatogonia stage. To evaluate the SPI index, seminiferous tubules containing spermatozoa in their lumen were considered as the tubes with positive spermatogenic index and tubules without spermatozoa in their lumen were considered as the tubes with negative spermatogenic index. To calculate the MI, the number of round spermatid cells and the primary spermatocytes in each lumen were counted, and calculated based on the ratio of round spermatid cells to the primary spermatocytes and the SCI was calculated by dividing the number of the germ cells into the number of the Sertoli cells (Sadeghzadeh et al.2019).
ADAMTS1 and ADAMTS5 metalloproteases produced by Sertoli cells: a potential diagnostic marker in azoospermia
Published in Systems Biology in Reproductive Medicine, 2019
Oya Sena Aydos, Yunus Yukselten, Sinan Ozkavukcu, Asuman Sunguroglu, Kaan Aydos
Sertoli cells of OA cases that were used as the control group, diagnosed with azoospermia due to a defect in excretory canals with no pathology in their seminiferous tubule epithelium, displayed higher levels of ADAMTS1 and ADAMTS5 proteins than NOA patients. Our data show the importance of these proteins for spermatogenesis and spermiogenesis in normal physiology. Although there is no enlightening study on this subject, it is known that MMPs as a family of ECM-degrading enzymes may have a role: i) in the migration of differentiating cells toward the lumen and ii) in the formation of blood–testis barrier by controlling Sertoli–Sertoli and Sertoli–germ cell relationships (Cheng and Mruk 2012). Animal models with silenced ADAMTS1 and ADAMTS5 can provide data that would inform about the specific roles of these proteins (Jacobsen and Wewer 2009). Moreover, the underlying cause of lower expression of these proteins in patients with NOA, compared with the controls, can be due to hormonal factors or paracrine factors localized in the testis (changes in blood supply, interaction of paracrine and autocrine factors, toxins, changes in testicular temperature, etc.) (Russel 1993; Sharpe 2000; Russel et al. 2015).