In vitro culture of functionally active buffalo hepatocytes isolated by using a simplified manual perfusion method

Short Culture of Bovine Hepatocytes Biopsied from Dairy Cows as a Model for Toxicological Studies-CYP 1A1 Activity Response to Zearalenone Treatment

This study presents a simple and cost-effective method for isolating hepatocytes from liver biopsies obtained from healthy and ketotic dairy cows, which can be utilized for studying cellular metabolism, drug toxicity, and hepatocyte-specific gene function and regulation. The expression of hepatocyte marker genes (G6PC, ALB, CYP1A2) was measured and found to be highest at 6 h post-isolation, with a subsequent decrease over time. Cells isolated from ketotic livers exhibited lower expression levels than those from healthy livers. Furthermore, for the functional characterization of ketotic hepatocytes, the cells were exposed to varying doses of zearalenone (ZEA). While doses of 10-50 µM did not affect cell viability, the highest dose of ZEA (100 µM) significantly decreased cell viability, as measured using XTT assay. Additionally, the potential induction of cytochrome P450 A1 (CYP1A1) by ZEA was found. Despite limitations such as a short-term culture, this model provides a useful tool for conducting toxicological research.

Tumor necrosis factor alpha and palmitate simulate bovine fatty liver disease in vitro when using abattoir-derived primary bovine hepatocytes isolated by a novel nonperfusion method

Hepatic lipidosis (i.e., fatty liver) is a common periparturient disease in high-producing dairy cattle affecting nearly 50% of cows to some degree and costing an estimated 60 million dollars annually. Large animal studies are costly, labor intensive, and are not well suited to mechanistic studies. Traditionally, mechanistic studies employ in vitro methodologies, utilizing established cell lines or primary cell culture methods. However, with dairy cattle, established hepatic cell lines do not exist, and methods for primary cell culture studies typically involve complicated procedures that often utilize very young animals (typically bull calves). Several previously published papers have used abattoir-derived tissues as a source of primary cells; however, a simple method utilizing simple culture media has yet to be presented. In addition, we sought to develop a way to replicate the syndrome of fatty liver disease "in a dish" using adult cattle that should more closely represent the physiology of the periparturient dairy cow. Herein we present a non-perfusion-based method that results in robust growth and proliferation of abattoir-derived bovine hepatocytes that demonstrate lipid loading, elevated lactate dehydrogenase leakage, and cytotoxicity as demonstrated by elevated caspase 3/7 expression consistent with in vivo physiology of the periparturient dairy cow with fatty liver disease.

Establishing a model of primary bovine hepatocytes with responsive growth hormone receptor expression

The liver becomes resistant to growth hormone before parturition in dairy cows (uncoupling of the somatotropic axis). However, the mechanism of growth hormone insensitivity has not been fully described. The aim of the present study was to improve a previous model of adult bovine hepatocytes in a sandwich culture system to ensure growth hormone receptor (GHR) expression. First, we modified the protocol for hepatocyte retrieval and tested the effect of short (18 min) and long (up to 30 min) warm ischemia on hepatocyte viability. Second, we used medium additives that affect GHR expression in vivo-insulin (INS), dexamethasone (DEX), both (INS+DEX), or no hormone additives (CTRL)-to ensure the functionality of hepatocytes, as measured by lactate dehydrogenase activity and urea concentration in the medium. We also used reverse transcriptase PCR of hepatocytes to evaluate expression of albumin (ALB), hepatocyte nuclear factor 4α (HNF4A), nuclear factor-κ-B-inhibitor α (NFKBIA), cytosolic phosphoenolpyruvate carboxykinase (PCK1), and vimentin (VIM) mRNA. Moreover, we analyzed the expression of GHRtot (GHR), GHR1A, insulin-like growth factor-1 (IGF1), and IGF binding protein-2 (IGFBP2) in response to exposure to media with the different compositions. Modification of the protocol (changes in rinsing and perfusion times, buffer composition, and the volume and standardization of collagenase) led to increased cell counts and cell viability. Short warm ischemia with the modified protocol significantly increased cell count (4.7 × 10⁷ ± 1.9 × 10⁷ vs. 3.5 × 10⁶ ± 1.5 × 10⁶ vital cells/g of liver) and viability (79.1 ± 8.4 vs. 37.1 ± 8.9%). Therefore, we gathered hepatocytes from the liver after short warm ischemia with the modified protocol. For these hepatocytes, lactate dehydrogenase activity was lower in media with INS and with DEX than in media with INS+DEX or CTRL; urea concentrations were highest at d 4 for INS+DEX. As well, HNF4A and ALB were more highly expressed in hepatocytes cultured with INS and INS+DEX than in those cultured with DEX or CTRL, and the substitution of DEX suppressed VIM and NFKBIA expression but increased PCK1 expression. The expression of GHR, GHR1A, and IGF1 was suppressed by dexamethasone (DEX and INS+DEX), whereas INS distinctly increased GHR, GHR1A, and IGF1 mRNA expression. Hepatocytes in a sandwich culture showed influenceable GHR expression; this study provides a model that can be used in studies examining factors that influence the expression and signal transduction of GHR in dairy cows.

Hanging Drop, A Best Three-Dimensional (3D) Culture Method for Primary Buffalo and Sheep Hepatocytes

Livestock, having close resemblance to humans, could be a better source of primary hepatocytes than rodents. Herein, we successfully developed three-dimensional (3D) culturing system for primary sheep and buffalo hepatocytes. The 3D-structures of sheep hepatocytes were formed on the fifth-day and maintained until the tenth-day on polyHEMA-coated plates and in hanging drops with William’s E media (HDW). Between the cultured and fresh cells, we observed a similar expression of GAPDH, HNF4α, ALB, CYP1A1, CK8 and CK18. Interestingly, a statistically significant increase was noted in the TAT, CPS, AFP, AAT, GSP and PCNA expression. In buffalo hepatocytes culture, 3D-like structures were formed on the third-day and maintained until the sixth-day on polyHEMA and HDW. The expression of HNF4α, GSP, CPS, AFP, AAT, PCNA and CK18 was similar between cultured and fresh cells. Further, a statistically significant increase in the TAT and CK8 expression, and a decrease in the GAPDH, CYP1A1 and ALB expression were noted. Among the culture systems, HDW maintained the liver transcript markers more or less similar to the fresh hepatocytes of the sheep and buffalo for ten and six days, respectively. Taken together, hanging drop is an efficient method for 3D culturing of primary sheep and buffalo hepatocytes.

Isolation and cultivation of adult primary bovine hepatocytes from abattoir derived liver

The aim was to establish a cell culture of adult primary bovine hepatocytes obtained from liver following slaughter and to cultivate the cells in a sandwich culture. Cells and medium samples were taken after separation of cells (day 0), during monolayer (days 1, 2 and 3) and during sandwich culture (days 1, 2, 3, 4, 7, 10 and 14). The mRNA expression of BAX, BCL2L, FAS, IGF-1 and GHR1A was measured as well as urea and LDH. Hepatocytes were obtained by using a two-step collagenase perfusion and were purified thereafter by density gradient centrifugation. The viability was 68.2 ± 9.5 %. In sandwich culture, cells have a typical polygonal hepatocyte-like shape, build cell-cell contacts, and show irregularity of cell borders suggesting bile canaliculi generation. The BAX mRNA expression increased on day 1 as well but decreased steadily until day 3 and remained constant for 14 days. Urea- and LDH-concentrations increased from day 4 to day 7. In conclusion, we found that it is possible to gather viable primary hepatocytes from adult bovine liver after slaughter, and that cells gathered this way show typical morphologies, urea-production and low LDH-leakage especially at day 4 in a sandwich system.