G. Saikumar

Isolation, culture and characterization of caprine mesenchymal stem cells derived from amniotic fluid

Amniotic fluid (AF) represents heterologous cell types and a specific group of these cells show high growth rate and multipotent characteristics. The aim of the present study was to culture and fully characterize the putative stem cell population isolated from caprine mesenchymal stem cells. Plastic adherent fibroblastoid cell population could be successfully isolated from the caprine amniotic fluid. In vitro expanded caprine amniotic fluid derived mesenchymal stem cells (cAF-MSCs) showed high proliferation ratio with a doubling time of 33.1h and stained positive for alkaline phosphatase. Relative transcript abundance of CD-73, CD-90 and CD-105 surface markers were analyzed by SYBR green based real time PCR and their respective proteins were localized through immunocytochemistry, however cAF-MSCs were found negative for haematopoietic marker CD-34. When exposed to corresponding induction condition, cAF-MSCs differentiated into osteogenic, adipogenic and chondrogenic lineages which was confirmed through von Kossa, Oil Red O and Alcian blue staining respectively. Furthermore, these cells were found positive for undifferentiated embryonic stem cell markers like Oct-4, Nanog, Sox-2, SSEA-1 and SSEA-4 which accentuate their pluripotent property. In conclusion, caprine amniotic fluid represents a promising source of mesenchymal stem cells with high proliferative and differentiation potential and these cells offer their scope for multiple regenerative therapies.

Expression of nitric oxide synthase isoforms in different stages of buffalo (Bubalus bubalis) ovarian follicles: effect of nitric oxide on in vitro development of preantral follicle.

The present study was designed to investigate the expression of nitric oxide synthase (NOS) isoforms in buffalo ovarian preantral (PFs), antral (AFs) and ovulatory (OFs) follicles (Experiment 1); effect of NO on in vitro survival and growth of PFs (Experiment 2) and NOS activity in immature oocytes by NADPH-diaphorase test (Experiment 3). In Experiment 1, NOS isoforms (neuronal, inducible and endothelial) were localized immunohistochemically; mRNA and protein expression was analyzed by semi-quantitative RT-PCR and western blot, respectively. In Experiment 2, PFs were isolated by micro-dissection method from buffalo ovaries and cultured in 0 (control), 10(-3), 10(-5), 10(-7) and 10(-9) M sodium nitroprusside (SNP). PFs were further cultured with 10(-5) M SNP + 1.0 mM N(ω)-nitro-L-arginine methyl ester (L-NAME) or 1.0 μg/ml hemoglobin (Hb) to examine the reversible effect of SNP. Immunohistochemical studies demonstrated that inducible nitric oxide synthase (iNOS) immunoreactivity was predominantly localized in granulosa and theca cells whereas, neuronal (nNOS) and endothelial (eNOS) nitric oxide synthase in the theca, granulosa and cumulus cells of PFs, AFs and OFs. The amount of mRNA as well as protein of nNOS and eNOS was found similar between different stages of follicles. In contrast, higher level of iNOS mRNA was observed in OFs and protein in the AFs. Higher doses of SNP (10(-3), 10(-5), 10(-7) M) inhibited (P < 0.05) while, lower dose of SNP (10(-9) M) stimulated (P < 0.05) the survival, growth, and antrum formation of PFs. The inhibitory effects of SNP were reversed by Hb, while L-NAME was not found effective. In conclusion, expression of NOS isoforms mRNA and protein in PFs, AFs, and OFs and NOS enzyme activity in immature follicular oocytes suggest a role for NO during ovarian folliculogenesis in buffalo. NO plays a dual role on growth and survival of PFs depending on its concentration in the culture medium.

Molecular and cellular characterization of buffalo bone marrow-derived mesenchymal stem cells.

Immune privileged mesenchymal stem cells (MSCs) can differentiate into multiple cell types and possess great potential for human and veterinary regenerative therapies. This study was designed with an objective to isolate, expand and characterize buffalo bone marrow-derived MSCs (BM-MSCs) at molecular and cellular level. Buffalo BM-MSCs were isolated by Ficoll density gradient method and cultured in Dulbeccos modified Eagles medium supplemented with fetal bovine serum (FBS). These cells were characterized through alkaline phosphatase (AP) staining, colony-forming unit (CFU) assay, mRNA expression analysis (CD 73, CD 90, CD 105, Oct4 and Nanog), immunolocalization along with flow cytometry (Stro 1, CD 73, CD 105, Oct4, Sox2 and Nanog) and in situ hybridization (Oct4 and Sox2). Multilineage differentiation (osteogenic, adipogenic and chondrogenic) was induced in vitro, which was further assessed by specific staining. Buffalo BM-MSCs have the capacity to form plastic adherent clusters of fibroblast-like cells and were successfully maintained up to 16(th) passage. These cells were AP positive, and further CFU assay confirmed their clonogenic property. RT-PCR analysis and protein localization study showed that buffalo BM-MSCs are positive for various cell surface markers and pluripotency markers. Cytoplasmic distribution of mRNA for pluripotency markers in buffalo BM-MSCs and multilineage differentiation were induced in vitro, which was further assessed by specific staining. To the best of our knowledge, this is the first report of buffalo BM-MSCs, which suggests that MSCs can be derived and expanded from buffalo bone marrow and can be used after characterization as a novel agent for regenerative therapy.

Prebiotic potential of Jerusalem artichoke (Helianthus tuberosus L.) in Wistar rats: effects of levels of supplementation on hindgut fermentation, intestinal morphology, blood metabolites and immune response

BACKGROUND Many studies have been conducted using purified prebiotics such as inulin or fructooligosaccharides (FOS) as nutraceuticals, but there is very little information available on the prebiotic potential of raw products rich in inulin and FOS, such as Jerusalem artichoke (JA; Helianthus tuberosus L.). The present experiment aimed to evaluate the prebiotic effects of JA tubers in rats. RESULTS Seventy-two Wistar weanling rats divided into four groups were fed for 12 weeks on a basal diet fortified with pulverized JA tubers at 0 (control), 20, 40 and 60 g kg(-1) levels. Enhanced cell-mediated immunity in terms of skin indurations (P = 0.082) and CD4+ T-lymphocyte population (P = 0.002) was observed in the JA-supplemented groups compared with the control group. Blood haemoglobin (P = 0.017), glucose (P = 0.001), urea (P = 0.004) and calcium (P = 0.048) varied favourably upon inclusion of JA. An increasing trend (P = 0.059) in the length of large intestine was apparent in the JA-fed groups. The tissue mass of caecum (P = 0.069) and colon (P = 0.003) was increased in the JA-supplemented groups, accompanied by higher (P = 0.007) caecal crypt depth. The pH and ammonia concentrations of intestinal digesta decreased and those of lactate and total volatile fatty acids increased in the JA-fed groups. CONCLUSION The results suggest that JA had beneficial effects on immunity, blood metabolites, intestinal morphometry and hindgut fermentation of rats.

Expression and characterization of constitutive heat shock protein 70.1 (HSPA-1A) gene in in vitro produced and in vivo-derived buffalo (Bubalus bubalis) embryos.

Cells are blessed with a group of stress protector molecules known as heat shock proteins (HSPs), amongst them HSP70, encoded by HSPA-1A gene, is most abundant and highly conserved protein. Variety of stresses hampers the developmental competence of embryos under in vivo and in vitro conditions. Present work was designed to study the quantitative expression of HSPA-1A mRNA in immature oocytes (IMO), matured oocytes (MO), in vitro produced (IVP) and in vivo-derived (IVD) buffalo embryos to assess the level of stress to which embryos are exposed under in vivo and in vitro culture conditions. Further, HSPA-1A gene sequence was analysed to determine its homology with other mammalian sequences. The mRNA expression analysis was carried out on 72 oocytes (40 IMO; 32 MO), 76 IVP and 55 IVD buffalo embryos. Expression of HSPA-1A was found in oocytes and throughout the developmental stages of embryos examined irrespective of the embryo source; however, higher (p < 0.05) expression was observed in 8-16 cell, morula and blastocyst stages of IVP embryos as compared to IVD embryos. Phylogenetic analysis of bubaline HSPA-1A revealed that it shares 91-98% identity with other mammalian sequences. It can be concluded that higher level of HSPA-1A mRNA in IVP embryos in comparison with in vivo-derived embryos is an indicator of cellular stress in IVP system. This study suggests need for further optimization of in vitro culture system in which HSPA-1A gene could be used as a stress biomarker during pre-implantation development.

A Comparative Study of Growth Kinetics, In Vitro Differentiation Potential and Molecular Characterization of Fetal Adnexa Derived Caprine Mesenchymal Stem Cells.

The present study was conducted with an objective of isolation, in vitro expansion, growth kinetics, molecular characterization and in vitro differentiation of fetal adnexa derived caprine mesenchymal stem cells. Mid-gestation gravid caprine uteri (2–3 months) were collected from abattoir to derive mesenchymal stem cells (MSCs) from fetal adnexa {amniotic fluid (cAF), amniotic sac (cAS), Wharton’s jelly (cWJ) and cord blood (cCB)} and expanded in vitro. These cultured MSCs were used at the 3rd passage (P3) to study growth kinetics, localization as well as molecular expression of specific surface antigens, pluripotency markers and mesenchymal tri-lineage differentiation. In comparison to cAF and cAS MSCs, cWJ and cCB MSCs showed significantly (P<0.05) higher clonogenic potency, faster growth rate and low population doubling (PDT) time. All the four types of MSCs were positive for alkaline phosphatase (AP) and differentiated into chondrogenic, osteogenic, and adipogenic lineages. These stem cells expressed MSC surface antigens (CD73, CD90 and CD105) and pluripotency markers (Oct4, Sox2, Nanog, KLF, cMyc, FoxD3) but did not express CD34, a hematopoietic stem cell marker (HSC) as confirmed by RT-PCR, immunocytochemistry and flow cytometric analysis. The relative mRNA expression of MSC surface antigens (CD73, CD90 and CD105) was significantly (P<0.05) higher in cWJ MSCs compared to the other cell lines. The mRNA expression of Oct4 was significantly (P<0.05) higher in cWJ, whereas mRNA expression of KLF and cMyc was significantly (P<0.05) higher in cWJ and cAF than that of cAS and cCB. The comparative assessment revealed that cWJ MSCs outperformed MSCs from other sources of fetal adnexa in terms of growth kinetics, relative mRNA expression of surface antigens, pluripotency markers and tri-lineage differentiation potential, hence, these MSCs could be used as a preferred source for regenerative medicine.

Expression and quantification of Oct-4 gene in blastocyst and embryonic stem cells derived from in vitro produced buffalo embryos

The POU-domain transcription factor Pou5f1 (Oct-4) is involved in transcriptional regulation during early embryonic development and cell differentiation. Despite highly conserved genomic organization of Oct-4 gene in mammals, expression pattern of Oct-4 is highly variable in different species. In the present study, expression pattern of Oct-4 in buffalo blastocyst, trophoectoderm (TE), and embryonic stem cells (ESCs) was investigated. For the derivation and characterization of buffalo ESCs, inner cell masses (ICMs) were isolated from 18 hatched and 21 expanded in vitro produced buffalo blastocyst and cultured over mitomycin-C-treated buffalo fetal fibroblast feeder layer. Alkaline phosphatase (AP) activity, SSEA-1 and 4, TRA 1–60 and 1–81, and Oct-4 proteins were localized in ICM, TE, and ESCs. Quantification of Oct-4 was done by amplifying a transcript of 125 base pairs by real-time polymerase chain reaction. Primary cell colony formation was higher (P < 0.05) in hatched blastocyst (83.33%, 15/18) compared to mechanically isolated ICMs from expanded blastocyst (52.38%, 11/21). Undifferentiated buffalo ESCs were positive for AP and expressed Oct-4, SSEA-1 and 4, TRA-1–60, and TRA-1–81 proteins. Oct-4 transcripts and proteins were detected in the ICM, TE cells and were invariably present in ESCs; however, expression level of Oct-4 transcript were significantly higher in ICM and ESCs as compared to TE cells. In conclusion, expression of Oct-4 is not only restricted to the ICM and ESCs but its expression was also detected in TE cells suggesting that instead of using Oct-4 as a single marker, it is better to have other flanking molecular markers for the identification of buffalo pluripotent embryonic stem cells.

Expression of mRNA Encoding IGF-I, IGF-II, Type-I, and II IGF-Receptors and IGF-Binding Proteins-1-4 during Ovarian Follicular Development in Buffalo (Bubalus bubalis)

The present study was designed to investigate the expression pattern of IGF-I, IGF-II, type-I and II IGF-receptors, and IGFBP-1-4 in different stages of buffalo ovarian preantral follicles (PFs), antral follicles (AFs), ovulatory follicles (OFs), and immature (IM) and in vitro matured (MO) oocytes. Buffalo ovaries were collected from local abattoir, PFs (200-250 µm), AFs (1-3 mm), and OFs (5-8 mm) were isolated by mechanical method. PFs, AFs, OFs, and oocytes were lysed to release mRNA, reverse transcribed, and then subjected to RT-PCR, whereas protein were localized through immunohistochemistry. Relative expression of mRNA transcripts was clearly seen for IGF-II, type-I and II IGF-receptors, and IGFBP-1-4 in all the stages of developing follicles and oocytes. We were unable to detect mRNA and protein expression of IGF-1 in any of the oocytes or follicles at any stage of the development. IGF-II and both IGF receptors mRNA expression were found higher (P < 0.05) in PFs compared to AFs and OFs. Expression of IGFBP-1 and 2 in PFs, as well as IGFBP-3 and 4 in AFs, was found with higher (P < 0.05) levels. The expression results were further confirmed by localization of IGF-II, type-I and II IGF-receptors, and IGFBP-1-4 proteins. In conclusion, IGF-II appears to be the only ligand that is endogenously expressed by all the follicular stages and oocytes, which may act in an autocrine manner through the Type-1 IGF receptor. Expression of IGFBP-1-4 and IGF-II suggests the possible role of these genes in recruitment, growth, proliferation, and steroidogenic responses during developmental phases of buffalo ovarian follicles.

Impact of oocyte-secreted factors on its developmental competence in buffalo

Oocyte-secreted factors (OSFs) play an important role in the acquisition of oocyte developmental competence through bidirectional cross-talk between oocyte and cumulus cells via gap junctions. Thus, the present study was designed to investigate the effect of two OSFs, growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15), on the developmental competence of buffalo oocytes derived from two different follicle sizes. Cumulus-oocyte complexes (COCs) from large follicles (LF, >6 mm) or small follicles (SF, 0.05) between DOs and combination groups. Relative mRNA analysis revealed significantly higher (P > 0.05) expression of the cumulus cell marker genes EGFR, HAS2, and CD44 in LF-derived than SF-derived oocyte; the expression of these markers was significantly higher (P > 0.05) in DOs and combination groups, irrespective of the follicle size. These results suggested that LF-derived oocytes have a higher developmental competence than SF-derived oocytes and that supplementation of GDF9 and BMP15 modulates the developmental competence of buffalo oocytes by increasing the relative abundance of cumulus-enabling factors and thereby increasing cleavage and the quality of blastocyst production.

Impact of Cryopreservation on Caprine Fetal Adnexa Derived Stem Cells and Its Evaluation for Growth Kinetics, Phenotypic Characterization, and Wound Healing Potential in Xenogenic Rat Model

This study was conducted to know the impact of cryopreservation on caprine fetal adnexa derived mesenchymal stem cells (MSCs) on the basic stem cell characteristics. Gravid caprine uteri (2–3 months) were collected from local abattoir to derive (amniotic fluid [cAF], amniotic sac [cAS], Whartons jelly [cWJ], and cord blood [cCB]) MSCs and expanded in vitro. Cells were cryopreserved at 3rd passage (P3) using 10% DMSO. Post‐thaw viability and cellular properties were assessed. Cells were expanded to determine growth kinetics, tri‐lineage differentiation, localization, and molecular expression of MSCs and pluripotency markers; thereafter, these cells were transplanted in the full‐thickness (2 × 2cm2) rat skin wound to determine their wound healing potential. The post‐thaw (pt) growth kinetics study suggested that cWJ MSCs expanded more rapidly with faster population doubling time (PDT) than that of other fetal adnexa MSCs. The relative mRNA expression of surface antigens (CD73, CD90, and CD 105) and pluripotency markers (Oct4, KLF, and cMyc) was higher in cWJ MSCs in comparison to cAS, cAF, and cCB MSCs post‐thaw. The percent wound contraction on 7th day was more than 50% for all the MSC‐treated groups (pre and post‐thaw), against 39.55% in the control group. On day 28th, 99% and more wound contraction was observed in cAF, cAF‐pt, cAS‐pt, cWJ, cWJ‐pt, and cCB, MSCs with better scores for epithelization, neovascularization, and collagen characteristics at a non‐significant level. It is concluded that these MSCs could be successfully cryopreserved without altering their stemness and wound healing properties. J. Cell. Physiol. 232: 2186–2200, 2017.