Unraveling the significance of PPP1R1A gene in pancreatic β-cell function: A study in INS-1 cells and human pancreatic islets

BACKGROUND AND AIMS

The protein phosphatase 1 regulatory inhibitor subunit 1A (PPP1R1A) has been linked with insulin secretion and diabetes mellitus. Yet, its full significance in pancreatic β-cell function remains unclear. This study aims to elucidate the role of the PPP1R1A gene in β-cell biology using human pancreatic islets and rat INS-1 (832/13) cells.

RESULTS

Disruption of Ppp1r1a in INS-1 cells was associated with reduced insulin secretion and impaired glucose uptake; however, cell viability, ROS, apoptosis or proliferation were intact. A significant downregulation of crucial β-cell function genes such as Ins1, Ins2, Pcsk1, Cpe, Pdx1, Mafa, Isl1, Glut2, Snap25, Vamp2, Syt5, Cacna1a, Cacna1d and Cacnb3, was observed upon Ppp1r1a disruption. Furthermore, silencing Pdx1 in INS-1 cells altered PPP1R1A expression, indicating that PPP1R1A is a target gene for PDX1. Treatment with rosiglitazone increased Ppp1r1a expression, while metformin and insulin showed no effect. RNA-seq analysis of human islets revealed high PPP1R1A expression, with α-cells showing the highest levels compared to other endocrine cells. Muscle tissues exhibited greater PPP1R1A expression than pancreatic islets, liver, or adipose tissues. Co-expression analysis revealed significant correlations between PPP1R1A and genes associated with insulin biosynthesis, exocytosis machinery, and intracellular calcium transport. Overexpression of PPP1R1A in human islets augmented insulin secretion and upregulated protein expression of Insulin, MAFA, PDX1, and GLUT1, while silencing of PPP1R1A reduced Insulin, MAFA, and GLUT1 protein levels.

CONCLUSION

This study provides valuable insights into the role of PPP1R1A in regulating β-cell function and glucose homeostasis. PPP1R1A presents a promising opportunity for future therapeutic interventions.

Investigating the Impact of IL6 on Insulin Secretion: Evidence from INS-1 Cells, Human Pancreatic Islets, and Serum Analysis

Interleukin-6 (IL6) is a pleiotropic cytokine implicated in metabolic disorders and inflammation, yet its precise influence on insulin secretion and glucose metabolism remains uncertain. This study examined IL6 expression in pancreatic islets from individuals with/without diabetes, alongside a series of functional experiments, including siRNA silencing; IL6 treatment; and assessments of glucose uptake, cell viability, apoptosis, and expression of key β-cell genes, which were conducted in both INS-1 cells and human islets to elucidate the effect of IL6 on insulin secretion. Serum levels of IL6 from Emirati patients with type 2 diabetes (T2D) were measured, and the effect of antidiabetic drugs on IL6 levels was studied. The results revealed that IL6 mRNA expression was higher in islets from diabetic and older donors compared to healthy or young donors. IL6 expression correlated negatively with PDX1, MAFB, and NEUROD1 and positively with SOX4, HES1, and FOXA1. Silencing IL6 in INS-1 cells reduced insulin secretion and glucose uptake independently of apoptosis or oxidative stress. Reduced expression of IL6 was associated with the downregulation of Ins, Pdx1, Neurod1, and Glut2 in INS-1 cells. In contrast, IL6 treatment enhanced insulin secretion in INS-1 cells and human islets and upregulated insulin expression. Serum IL6 levels were elevated in patients with T2D and associated with higher glucose, HbA1c, and triglycerides, regardless of glucose-lowering medications. This study provides a new understanding of the role of IL6 in β-cell function and the pathophysiology of T2D. Our data highlight differences in the response to IL6 between INS-1 cells and human islets, suggesting the presence of species-specific variations across different experimental models. Further research is warranted to unravel the precise mechanisms underlying the observed effects of IL-6 on insulin secretion.

Fat mass and obesity-associated (FTO) gene is essential for insulin secretion and β-cell function: In vitro studies using INS-1 cells and human pancreatic islets

AIMS

In this study, we investigated the role of the FTO gene in pancreatic β-cell biology and its association with type 2 diabetes (T2D). To address this issue, human pancreatic islets and rat INS-1 (832/13) cells were used to perform gene silencing, overexpression, and functional analysis of FTO expression; levels of FTO were also measured in serum samples obtained from diabetic and obese individuals.

RESULTS

The findings revealed that FTO expression was reduced in islets from hyperglycemic/diabetic donors compared to normal donors. This reduction correlated with decreased INS and GLUT1 expression and increased PDX1, GCK, and SNAP25 expression. Silencing of Fto in INS-1 cells impaired insulin release and mitochondrial ATP production and increased apoptosis in pro-apoptotic cytokine-treated cells. However, glucose uptake and reactive oxygen species production rates remained unaffected. Downregulation of key β-cell genes was observed following Fto-silencing, while Glut2 and Gck were unaffected. RNA-seq analysis identified several dysregulated genes involved in metal ion binding, calcium ion binding, and protein serine/threonine kinase activity. Furthermore, our findings showed that Pdx1 or Mafa-silencing did not influence FTO protein expression. Overexpression of FTO in human islets promoted insulin secretion and upregulated INS, PDX1, MAFA, and GLUT1 expression. Serum FTO levels did not significantly differ between individuals with diabetes or obesity and their healthy counterparts.

CONCLUSION

These findings suggest that FTO plays a crucial role in β-cell survival, metabolism, and function and point to a potential therapeutic utility of FTO in T2D patients.

Evaluation of automated monitoring calving prediction in dairy buffaloes a new tool for calving management

Abstract Buffalo is one of the leading milk-producing dairy animals. Its production and reproduction are affected due to some factors including inadequate monitoring around parturition, which cause economic losses like delayed birth process, increased risk of stillbirth, etc. The appropriate calving monitoring is essential for dairy herd management. Therefore, we designed a study its aim was, to predict the calving based on automated machine measured prepartum behaviors in buffaloes. The data were collected from n=40 pregnant buffaloes of 2nd to 5th parity, which was synchronized. The NEDAP neck and leg logger tag was attached to each buffalo at 30 days before calving and automatically collected feeding, rumination, lying, standing, no. of steps, no. of switches from standing to lying (lying bouts) and total motion activity. All behavioral data were reduced to -10 days before the calving date for statistical analysis to use mixed model procedure and ANOVA. Results showed that feeding and rumination time significantly (P<0.05) decreased from -10 to -1 days before calving indicating calving prediction. Moreover, Rumination time was at lowest (P<0.001) value at 2h before the calving such behavioral changes may be useful to predict calving in buffaloes. Similarly, lying bouts and standing time abruptly decreased (P<0.05) from -3 to -1 days before calving, while lying time abruptly increased (P<0.01) from -3 to -1 days before calving (531.57±23.65 to 665.62±18.14, respectively). No. of steps taken and total motion significantly (P<0.05) increased from -10 to -1 days before calving. Feeding time was significantly (P<0.02) lowered in 3rd parity buffaloes compared with 2nd, 4th and 5th parity buffaloes, while standing time of 5th parity buffaloes were lowered (P<0.05) as compared to 2nd to 4th parity buffalos at -1 day of prepartum. However, rumination, lying, no. of steps taken and total motion activity at -1 day of prepartum was independent (P>0.05) of parity in buffaloes. Neural network analysis for combined variables from NEDAP technology at the daily level yielded 100.0% sensitivity and 98% specificity. In conclusion NEDAP technology can be used to measured behavioral changes -10 day before calving as it can serve as a useful guide in the prediction calving date in the buffaloes.

Disrupting of family with sequence similarity 105, member A (Fam105a) deteriorates pancreatic β-cell physiology and insulin secretion in INS-1 cells

The role of "Family with sequence similarity 105, member A" (FAM105A) in pancreatic β-cell function in relation to type 2 diabetes mellitus (T2D) is not fully understood. To address this issue, various molecular and functional experiments were conducted on primary human islets and INS-1 cells. RNA-seq expression analysis showed that FAM105A is highly expressed in human islets and its expression is reduced in diabetic islets compared to healthy islets. FAM105A expression correlated negatively with HbA1c levels and body mass index (BMI). Co-expression analysis showed a significant correlation between FAM105A with PDX1, GCK, GLUT1 and INSR, but not the INS gene. Silencing of Fam105a impaired insulin release, content, glucose uptake, and mitochondria ATP content but did not affect cell viability, reactive oxygen species (ROS) or apoptosis levels. Silencing of Fam105a was associated with reduced Pdx1 and Glut2 expression at mRNA and protein levels. RNA-seq analysis of dysregulated genes in Fam105a-silenced cells showed an overall downregulation of gene expression in β-cells and insulin secretion pathway. Disrupting Pdx1 did not affect Fam105a expression in INS-1 cells. Overall, the results suggest that FAM105A plays an important role in pancreatic β-cells biology and may be involved in the development of T2D.

GDF15 plays a critical role in insulin secretion in INS-1 cells and human pancreatic islets

Mounting evidence points to a link between growth differentiation factor-15 (GDF15) expression and the onset and progression of diabetes mellitus. However, the exact role of GDF15 in pancreatic β-cell function is unclear. To examine the role of GDF15 in β-cell function, bioinformatics analysis and functional experiments involving GDF15 silencing and overexpression were performed in INS-1 cells and human islets. Public microarray and RNA-seq expression data showed that islets obtained from diabetic donors express high levels of GDF15 compared to islets obtained from normal donors. Moreover, analysis of RNA-seq expression data revealed that GDF15 expression correlates positively with that of insulin (INS), KCNJ11, GLUT1, MAFA, INSR and negatively with that of Glucokinase (GCK) and Alpha-Ketoglutarate Dependent Dioxygenase (FTO). No T2D-associated genetic variants in the GDF15 were found to pass genome-wide significance in the TIGER portal. Expression silencing of Gdf15 in INS-1 cells reduced insulin release, glucose uptake levels, increased reactive oxygen species (ROS) production and apoptosis levels. While Gdf15-silenced cells downregulated mRNA expression of Ins, Pdx1, Mafa, and Glut2 genes, its overexpression human islets was associated with increased insulin secretion and upregulated expression of MAFA and GLUT1 but not INS or GCK. Silencing of Pdx1 or Mafa in INS-1 cells did not affect the expression of GDF15. These findings suggest that GDF15 plays a significant role in pancreatic β-cell function.

Expression profiling of IL-1β, IL-6 and IL-8 genes in lung tissues of Aseel, Crossbred Naked neck, and White Leghorn chicken challenged with H9N2 Influenza virus

Aseel and Naked neck are major chicken breeds of the tropics and well-known for their thermotolerance and robustness. However, both of them especially Aseel are very susceptible to Avian Influenza (AI) which cause huge mortalities. The role of cytokines in relation to the pathology and severity of the disease caused by the endemic strain (H9N2) of AIV in these breeds remained thus far unclear. The aim of this study was to investigate the effects of H9N2 AIV on the expression level of IL-1β, IL-6 and IL-8 in the lung tissues of Aseel, crossbred Naked Neck, and White Leghorn (WLH). In total 60 birds, 20 from each breed, were used in this study, whereas 30 birds (10 from each breed) were challenged intranasally with H9N2 virus with a concentration of 106 EID50 at 6wk of age and other half were treated as control. The lung tissues were sampled at 5th day post-infection to study the differential expression of IL-1β, IL-6, and IL-8 using qRT-PCR. Our data revealed a significant difference (P<0.001) in the gene expression levels among all the breeds in response to viral challenge. It was also observed that after exposure to H9N2 virus, Aseel birds showed the highest increase in their expressions of interleukin (IL-1 β, IL-6, and IL-8) genes followed by Naked Neck and WLH respectively suggesting greater susceptibility of Aseel to AIV compared with other breeds. However, these results are in agreement with the severity of disease and incidence of mortality caused by AI in these breeds.

Reduced Retinoic Acid Receptor Beta (Rarβ) Affects Pancreatic β-Cell Physiology

Various studies have suggested a link between vitamin A (VA), all-trans-retinol, and type 2 diabetes (T2D). However, the functional role/expression of vitamin A receptors (Rarα, β, and γ) in pancreatic β-cells is not clear yet. Accordingly, we performed a series of bioinformatics, molecular and functional experiments in human islet and INS-1 cells to evaluate the role of Rarβ on insulin secretion and pancreatic β-cell function. Microarray and RNA-sequencing (RAN-seq) expression analysis showed that RARα, β, and γ are expressed in human pancreatic islets. RNA-seq expression of RARβ in diabetic/hyperglycemic human islets (HbA1c ≥ 6.3%) revealed a significant reduction (p = 0.004) compared to nondiabetic/normoglycemic cells (HbA1c < 6%). The expression of RARβ with INS and PDX1 showed inverse association, while positive correlations were observed with INSR and HbA1c levels. Exploration of the T2D knowledge portal (T2DKP) revealed that several genetic variants in RARβ are associated with BMI. The most associated variant is rs6804842 (p = 1.2 × 10−25). Silencing of Rarβ in INS-1 cells impaired insulin secretion without affecting cell viability or apoptosis. Interestingly, reactive oxygen species (ROS) production levels were elevated and glucose uptake was reduced in Rarβ-silenced cells. mRNA expression of Ins1, Pdx1, NeuroD1, Mafa, Snap25, Vamp2, and Gck were significantly (p < 0.05) downregulated in Rarβ-silenced cells. For protein levels, Pro/Insulin, PDX1, GLUT2, GCK, pAKT/AKT, and INSR expression were downregulated considerably (p < 0.05). The expression of NEUROD and VAMP2 were not affected. In conclusion, our results indicate that Rarβ is an important molecule for β-cell function. Hence, our data further support the potential role of VA receptors in the development of T2D.

Biomimetic Design of Artificial Hybrid Nanocells for Boosted Vascular Regeneration in Ischemic Tissues

Restoration of sufficient blood supply for the treatment of ischemia remains a significant scientific and clinical challenge. Here, a cell-like nanoparticle delivery technology is introduced that is capable of recapitulating multiple cell functions for the spatiotemporal triggering of vascular regeneration. Specifically, a copper-containing protein is successfully prepared using a recombinant protein scaffold based on a de novo design strategy, which facilitates the timely release of nitric oxide and improved accumulation of particles within ischemic tissues. Through closely mimicking physiological cues, the authors demonstrate the benefits of bioactive factors secreted from hypoxic stem cells on promoting angiogenesis. Following this cell-mimicking manner, artificial hybrid nanosized cells (Hynocell) are constructed by integrating the hypoxic stem cell secretome into nanoparticles with surface coatings of cell membranes fused with copper-containing protein. The Hynocell, hybridized with different cell-derived components, provides synergistic effects on targeting ischemic tissues and promoting vascular regeneration in acute hindlimb ischemia and acute myocardial infarction models. This study offers new insights into the utilization of nanotechnology to potentiate the development of cell-free therapeutics.

EXOC6 (Exocyst Complex Component 6) Is Associated with the Risk of Type 2 Diabetes and Pancreatic β-Cell Dysfunction

EXOC6 and EXOC6B (EXOC6/6B) components of the exocyst complex are involved in the secretory granule docking. Recently, EXOC6/6B were anticipated as a molecular link between dysfunctional pancreatic islets and ciliated lung epithelium, making diabetic patients more prone to severe SARS-CoV-2 complications. However, the exact role of EXOC6/6B in pancreatic β-cell function and risk of T2D is not fully understood. Herein, microarray and RNA-sequencing (RNA-seq) expression data demonstrated the expression of EXOC6/6B in human pancreatic islets. Expression of EXOC6/6B was not affected by diabetes status. Exploration of the using the translational human pancreatic islet genotype tissue-expression resource portal (TIGER) revealed three genetic variants (rs947591, rs2488071 and rs2488073) in the EXOC6 gene that were associated (p < 2.5 × 10−20) with the risk of T2D. Exoc6/6b silencing in rat pancreatic β-cells (INS1-832/13) impaired insulin secretion, insulin content, exocytosis machinery and glucose uptake without cytotoxic effect. A significant decrease in the expression Ins1, Ins1, Pdx1, Glut2 and Vamp2 was observed in Exoc6/6b-silenced cells at the mRNA and protein levels. However, NeuroD1, Gck and InsR were not influenced compared to the negative control. In conclusion, our data propose that EXOC6/6B are crucial regulators for insulin secretion and exocytosis machinery in β-cells. This study identified several genetic variants in EXOC6 associated with the risk of T2D. Therefore, EXOC6/6B could provide a new potential target for therapy development or early biomarkers for T2D.

Heme Oxygenase-1 (HMOX-1) and inhibitor of differentiation proteins (ID1, ID3) are key response mechanisms against iron-overload in pancreatic β-cells

Iron overload promotes the generation of reactive oxygen species (ROS). Pancreatic β-cells can counter oxidative stress through multiple anti-oxidant responses. Herein, RNA-sequencing was used to describe the expression profile of iron regulatory genes in human islets with or without diabetes. Functional experiments including siRNA silencing, qPCR, western blotting, cell viability, ELISA and RNA-sequencing were performed as means of identifying the genetic signature of the protective response following iron overload-induced stress in human islets and INS-1. FTH1 and FTL genes were highly expressed in human islets and INS-1 cells, while hepcidin (HAMP) was low. FXN, DMT1 and FTHL1 genes were differentially expressed in diabetic islets compared to control. Silencing of Hamp in INS-1 cells impaired insulin secretion and influenced the expression of β-cell key genes. RNA-sequencing analysis in iron overloaded INS-1 cells identified Id1 and Id3 as the top down-regulated genes, while Hmox1 was the top upregulated. Expression of ID1, ID3 and HMOX1 was validated at the protein level in INS-1 cells and human islets. Differentially expressed genes (DEGs) were enriched for TGF-β, regulating stem cells, ferroptosis, and HIF-1 signaling. Hmox1-silenced cells treated with FAC elevated the expression of Id1 and Id3 expression than untreated cells. Our findings suggest that HMOX1, ID1 and ID3 define the response mechanism against iron-overload-induced stress in β-cells.

Effects of production system and feeding regimen on carcass and meat quality traits of Naked Neck chicken

To evaluate the effect of a production system and feeding regimen on meat quality attributes of Naked Neck chickens, a total of 150 cockerels at 18 weeks old (1625 ± 70 g) were collected from 10 treatment groups with five replicates of three birds. The factorial arrangement of treatments consisted of two production systems (intensive and free-range) and five nutritional regimens, namely 100% commercial feed; 75% commercial feed plus 25% kitchen waste; 50% commercial feed plus 50% kitchen waste; 25% commercial feed plus 75% kitchen waste; and 100% kitchen waste. Carcass traits, meat quality, and meat organoleptic were found to differ significantly among production systems, feeding regimens, and their interaction. Higher liver weight was observed in birds reared under an intensive system. Higher gizzard weight was noted in birds fed with 100% kitchen waste, whereas lower gizzard weight was observed in birds fed the commercial diet. The meat from cockerels fed with 75% kitchen waste was most yellow, whereas the meat from the birds fed with 100% kitchen waste was least yellow. At two hours after slaughter, pH of the meat was highest in birds fed 50% kitchen waste and lowest in birds fed 100% kitchen waste. The interaction of production system and feeding regimen was significant for overall acceptability score. In conclusion, Naked Neck chickens performed equally well under intensive and free-range systems, irrespective of the level of kitchen waste that they were fed.

Nanozyme-Powered Giant Unilamellar Vesicles for Mimicry and Modulation of Intracellular Oxidative Stress

The bottom-up construction of enzyme-based artificial cells is generating increasing interest, but achieving artificial cells for "all artificial modules" remains challenging in synthetic biology. Here, we introduce a fully synthetic cell system by integration of biomimetic nanozymes into giant unilamellar vesicles (GUVs). To mimic native peroxidase for free radical generation by taking advantage of Fenton catalysis reactions, we designed and prepared a de novo artificial nanozyme composed of ferritin heavy-chain scaffold protein and catalytic Fe₃O₄ nanoparticles as the active center. As two examples in bioapplications, we showed this nanozyme-powered GUV system not only mimics intracellular oxidative stress pathways but also induces tumor cell death by sensing and responding to external chemical signals. Specifically, we recreated intracellular biochemical events, including DNA damage and lipid peroxidation, in the compartmentalized GUVs by taking advantage of nanozyme induction of defined catalytic reactions. Additionally, the GUV system also actively induced DNA double-strand breakage and lipid damage of tumor cells, in response to the high expression of H₂O₂ within the tumor microenvironment. This concept-of-proof study offers a promising option for defining catalysis in biological systems and gives new insights into the de novo creation of artificial cells in a fully synthetic manner.

Biomimetic Design of Mitochondria-Targeted Hybrid Nanozymes as Superoxide Scavengers

Development of enzyme mimics for the scavenging of excessive mitochondrial superoxide (O₂ ^•- ) can serve as an effective strategy in the treatment of many diseases. Here, protein reconstruction technology and nanotechnology is taken advantage of to biomimetically create an artificial hybrid nanozyme. These nanozymes consist of ferritin-heavy-chain-based protein as the enzyme scaffold and a metal nanoparticle core as the enzyme active center. This artificial cascade nanozyme possesses superoxide dismutase- and catalase-like activities and also targets mitochondria by overcoming multiple biological barriers. Using cardiac ischemia-reperfusion animal models, the protective advantages of the hybrid nanozymes are demonstrated in vivo during mitochondrial oxidative injury and in the recovery of heart functionality following infarction via systemic delivery and localized release from adhesive hydrogels (i.e., cardiac patch), respectively. This study illustrates a de novo design strategy in the development of enzyme mimics and provides a promising therapeutic option for alleviating oxidative damage in regenerative medicine.

Multifunctional Natural Polymer Nanoparticles as Antifibrotic Gene Carriers for CKD Therapy

BACKGROUND

Progressive fibrosis is the underlying pathophysiological process of CKD, and targeted prevention or reversal of the profibrotic cell phenotype is an important goal in developing therapeutics for CKD. Nanoparticles offer new ways to deliver antifibrotic therapies to damaged tissues and resident cells to limit manifestation of the profibrotic phenotype.

METHODS

We focused on delivering plasmid DNA expressing bone morphogenetic protein 7 (BMP7) or hepatocyte growth factor (HGF)-NK1 (HGF/NK1) by encapsulation within chitosan nanoparticles coated with hyaluronan, to safely administer multifunctional nanoparticles containing the plasmid DNA to the kidneys for localized and sustained expression of antifibrotic factors. We characterized and evaluated nanoparticles in vitro for biocompatibility and antifibrotic function. To assess antifibrotic activity in vivo, we used noninvasive delivery to unilateral ureteral obstruction mouse models of CKD.

RESULTS

Synthesis of hyaluronan-coated chitosan nanoparticles containing plasmid DNA expressing either BMP7 or NGF/NKI resulted in consistently sized nanoparticles, which-following endocytosis driven by CD44⁺ cells-promoted cellular growth and inhibited fibrotic gene expression in vitro. Intravenous tail injection of these nanoparticles resulted in approximately 40%-45% of gene uptake in kidneys in vivo. The nanoparticles attenuated the development of fibrosis and rescued renal function in unilateral ureteral obstruction mouse models of CKD. Gene delivery of BMP7 reversed the progression of fibrosis and regenerated tubules, whereas delivery of HGF/NK1 halted CKD progression by eliminating collagen fiber deposition.

CONCLUSIONS

Nanoparticle delivery of HGF/NK1 conveyed potent antifibrotic and proregenerative effects. Overall, this research provided the proof of concept on which to base future investigations for enhanced targeting and transfection of therapeutic genes to kidney tissues, and an avenue toward treatment of CKD.

Particle-based artificial three-dimensional stem cell spheroids for revascularization of ischemic diseases

Development of new approaches to biomimetically reconstruct vasculature networks remains challenging in regenerative medicine. We introduce a particle-based artificial stem cell spheroid (ASSP) technology that recapitulates paracrine functions of three-dimensional (3D) SSPs for vasculature regeneration. Specifically, we used a facile method to induce the aggregation of stem cells into 3D spheroids, which benefited from hypoxia microenvironment-driven and enhanced secretion of proangiogenic bioactive factors. Furthermore, we artificially reconstructed 3D spheroids (i.e., ASSP) by integration of SSP-secreted factors into micro-/nanoparticles with cell membrane-derived surface coatings. The easily controllable sizes of the ASSP particles provided superior revascularization effects on the ischemic tissues in hindlimb ischemia models through local administration of ASSP microparticles and in myocardial infarction models via the systemic delivery of ASSP nanoparticles. The strategy offers a promising therapeutic option for ischemic tissue regeneration and addresses issues faced by the bottlenecked development in the delivery of stem cell therapies.

Exploring nutritive profile, metabolizable energy, protein, and digestible amino acids contents of indigenous protein sources of different locations for male broilers

2 experiments were conducted to explore nutrient composition, AME, AMEn, standardized ileal digestibility (SID) of CP, and amino acids (AA) of 4 indigenous protein sources including canola meal (CM), rapeseed meal (RSM), guar meal (GM), and sunflower meal (SFM) collected from 2 different locations, Multan (MUL; n = 3) and Sukkur (SKR; n = 3), of Pakistan. Higher (P < 0.05) dry matter (DM), CP, and gross energy (GE), whereas lower (P < 0.05) ash contents were found in SKR, CM, and RSM compared with those from MUL. The MUL GM had higher (P < 0.05) crude fiber (CF) and CP, whereas lower (P < 0.05) GE compared with those from SKR. The SFM from MUL had higher DM, whereas lower CF and CP contents than SKR. In the first experiment, 216 21-d-old male broilers (Ross 308) were distributed over 8 test diets (4 ingredients × 2 locations) and 1 basal diet, with 4 replicates containing 6 birds each (9 × 4 × 6), in a complete randomized design to determine AME and AMEn. The results indicated higher (P < 0.05) AME and AMEn in MUL CM than SKR. In the second experiment, 216 21-d-old male broilers (Ross 308) were raised in 36 cages (6 birds each) to determine SID of CP and AA in a complete randomized design. 8 test diets (4 ingredients × 2 locations) and a protein-free diet, with 4 replicates each, were tested. The SID of CP and some AA were higher (P < 0.05) in MUL CM and RSM than SKR. The SKR GM had a higher (P < 0.05) SID of CP, arginine, methionine, threonine, valine, and cysteine compared with that from MUL. The SFM from MUL had higher (P < 0.05) SID of CP, arginine, histidine, methionine, valine, alanine, aspartate, cysteine, and serine than SKR. In conclusion, major differences do exist between CM, GM, RSM, and SFM from different locations in terms of nutrients, AME, digestible CP, and AA contents for male broilers.

Pharmacoinformatics and molecular docking reveal potential drug candidates against Schizophrenia to target TAAR6

Schizophrenia (SZ) is a complex disabling disorder that leads to the mental disability and afflicts 1% of the world's total population and placed in top ten medical disorders. In current work, bioinformatics analyses were carried out on Trace amine (TA)-associated receptor 6 (TAAR6) to recognize the potential drugs and compounds against SZ. Comparative modeling and threading-based approaches were utilized for the structure prediction of TAAR6. Fifty-nine predicted structures were evaluated by various model assessment techniques and final model having only eight amino acids in the outlier region and 98.5% overall quality factor was chosen for further pharmacoinformatics and molecular docking analyses. From an extensive literature review, 11 Food and Drug Administration (FDA) approved drugs were analyzed by computational techniques and Aripiprazole was found as the most effective drug against SZ by targeting TAAR6. Here, we report five novel molecules which exhibited the highest binding affinity, effective drug properties, and interestingly, observed better results than the approved selected drugs against SZ by targeting TAAR6. The docking analyses revealed that Arg-92, Trp-98, Gln-191, Thr-192, Ala-290, Cys-291, Tyr-293, and Glu-294 residues were observed as critical interacting residues in receptor-ligand interactions. Absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties, Lipinski rule of five, highest binding affinity coupled with virtual screening (VS), and pharmacophore modeling approach illustrated that aripiprazole (-8.6 kcal/mol) and TAAR6_0094 (-9.3 kcal/mol) are potential inhibitors for targeting TAAR6. It is suggested that schizophrenic patients have to use Aripiprazole for the medication of SZ by targeting TAAR6 and develop effective therapies by utilizing scrutinized novel compound.

Nutritional and therapeutic perspectives of Chia (Salvia hispanica L.): a review

The ancient grain is becoming enormously popular in modern food regimen in many countries; the higher proportion of α-linolenic acid makes chia the superb source of omega-3 fatty (about 65 % of the oil content). Omega-3 fatty acid has been associated with a large number of physiological functions in human body. Chia seed is a potential source of antioxidants with the presence of chlorogenic acid, caffeic acid, myricetin, quercetin, and kaempferol which are believed to have cardiac, hepatic protective effects, anti-ageing and anti-carcinogenic characteristics. It is also a great source of dietary fibre which is beneficial for the digestive system and controlling diabetes mellitus with higher concentration of beneficial unsaturated fatty acids, gluten free protein, vitamin, minerals and phenolic compounds. Therapeutic effects of chia in the control of diabetes, dyslipidaemia, hypertension, as anti-inflammatory, antioxidant, anti-blood clotting, laxative, antidepressant, antianxiety, analgesic, vision and immune improver is scientifically established.

Distribution, correlation, and source apportionment of selected metals in tannery effluents, related soils, and groundwater--a case study from Multan, Pakistan

In order to study the distribution, correlation, and apportionment of selected metals, the tannery effluent, related soil, and groundwater samples were collected from Multan, Pakistan, and analyzed on flame atomic absorption spectrophotometer. Among the selected metals, Na, Ca, K, Cr, and Mg revealed dominant concentrations with average values of 5,499, 945, 565, 209, and 107 mg/L and 2,634, 330, 484, 14.1, and 60.5 mg/L in the effluents and groundwater, respectively, whereas the mean metal levels in soil samples were 10,026, 6,726, 9,242, 476, and 9,857 mg/kg. Overall, the mean metal concentrations in the tannery effluents, groundwater, and related soils reveal following order, respectively: Na > Ca > K > Cr > Mg > Ni > Fe > Zn > Co > Pb > Mn > Cd; Na > K > Ca > Mg > Cr > Zn > Ni > Pb > Fe > Co > Mn > Cd; Na > Mg > K > Ca > Cr > Co > Ni > Fe > Pb > Mn > Zn > Cd. Generally, the metal distribution in tannery effluents, soils, and groundwater was found to be random as evidenced by large differences between mean and median values as well as considerably higher standard deviation and skewness values. The selected metal data were also subjected to correlation study to investigate the covariation of metal levels in the three media. The source apportionment of the metal data in the effluents, soils, and groundwater was carried out using principal component analysis in addition to basic statistical and correlation analyses. The source apportionment studies evidenced the gross contamination of groundwater and soils in the vicinity of tanning industrial units in Multan. The current mean metal levels in the soil and groundwater were found to be considerably higher compared with the background concentration levels and WHO guideline values.

Statistical source identification of metals in groundwater exposed to industrial contamination

Levels of selected metals Na, Ca, Mg, K, Fe, Mn, Cr, Co, Ni, Cd, Pb and Mn were estimated by flame atomic absorption spectrophotometry in groundwater samples from Kasur, a significant industrial city of Pakistan. Salient mean concentration levels were recorded for: Na (211 mg/l), Ca (187 mg/l), Mg (122 mg/l), K (87.7 mg/l), Fe (2.57 mg/l) and Cr (2.12 mg/l). Overall, the decreasing metal concentration order was: Na>Ca>Mg>K>Fe>Cr>Zn>Co>Pb>Mn>Ni>Cd. Significantly positive correlations were found between Na-Cr (r=0.553), Na-Mn (r=0.543), Mg-Fe (r=0.519), Mg-Cr (r=0.535), Pb-K (r=0.506) and Pb-Ni (r=0.611). Principal Component Analysis and Cluster Analysis identified tannery effluents as the main source of metal contamination of the groundwater. The present metal data showed that Cr, Pb and Fe levels were several times higher than those recommended for water quality by WHO, US-EPA, EU and Japan. The elevated levels of Cr, recorded as 21-42 fold higher compared with the recommended quality values, were believed to originate from the tanning industry of Kasur.

Multivariate analysis of trace metals in textile effluents in relation to soil and groundwater

This paper deals with the multivariate analysis of metal data in effluents, soil and groundwater to find the distribution and source identification of the selected metals in the three media. Samples were collected from three textile industries located in Hattar Industrial Estate, Pakistan. Metals were estimated by flame atomic absorption spectrophotometry. The results showed elevated levels of Cr, Pb, Ni, Co, Fe, Ca, Na, K and Zn in these media, following the order: soil>effluent>water. Principle component analysis (PCA) of the data showed that the textile effluents are contaminating the soil wherein Cr and Pb were dominant toxic metals having concentrations of 5.96 mg/kg and 4.46 mg/kg, respectively. Other toxic metals such as Co, Cd, Zn, Ni, Mn and Fe, were found to have common origin in the textile effluents. The correlation study along with linear regression and PCA, supported the fact that various elevated metal concentrations emerged from the textile industrial effluents ultimately leading to contamination of the soil and groundwater in their proximity. The estimated metal levels in the water/soil system are compared with the safe limits laid down by WHO.

Multivariate analysis of trace metal levels in tannery effluents in relation to soil and water: a case study from Peshawar, Pakistan

Tannery effluents and relevant ground water and soil samples collected from various tanning industries of Peshawar were analyzed for Na, Ca, K, Mg, Fe, Mn, Cr, Co, Cd, Ni, Pb and Zn by the AAS method. The metal concentration data for the three media are reported in terms of basic statistical parameters, metal-to-metal correlations and linear regression analyses. Metal distributions in the three media were quite divergent and showed non-normal distributions with high standard deviation and skewness parameters. Sodium exhibited the highest mean levels of 1,277mg/L, 881mg/L and 12,912mg/kg in the effluent, ground water and soil samples, respectively. Among other metals, Cr concentrations were 410mg/L, 0.145mg/L, 100mg/kg and Ca, 278mg/L, 64.8mg/L, and 2,285mg/kg in the effluent, ground water and soil samples, respectively. Some significant correlations were observed between effluent and soils in terms of Na, Cr, Ni, Co and Pb. The ground water-soil interrelationship suggested that Na levels in the soil and ground water were significantly correlated with each other (r=0.486, P<0.01). Similarly, Cr in the soil is strongly correlated with Ca in ground water (r=0.486, P<0.01). These results were duly supported by the linear regression analysis of data. The source identification studies conducted using Principal Component Analysis (PCA) and Cluster Analysis (CA) evidenced that ground water and soil were being contaminated by the toxic metals emanating from the tannery effluents.

Comparative metal distribution in hair of Pakistani and Libyan population and source identification by multivariate analysis

Using nitric acid-perchloric acid wet digestion based FAAS method ten selected metals (Cd, Co, Cr, Fe, K, Mn, Na, Ni, Pb and Zn) were determined in the scalp hair of male Pakistani and Libyan donors (n = 62), between 3-54 years age and residing in typical urban areas. The study was taken up to identify sources of metal distribution in two diverse population segments exposed to different environments. Sodium emerged with the highest mean hair concentration of 511.0 microg/g and 496.9 mug/g for Libyan and Pakistani donors respectively, followed by K, at 266.2 microg/g and 242.4 microg/g for the two donor categories. Cadmium showed the lowest mean hair concentration for both Pakistani (0.380 microg/g) and Libyan (0.530 microg/g) donors. Levels of Na, K, Pb, Cr and Cd were higher in hair of Libyan donors compared with Pakistani counterparts which showed higher comparative levels of Zn, Fe, Co, Ni and Mn. Strong metal-to-metal correlations were found between Na-K (r = 0.638) and Cd-Co (r = 0.574) for Pakistani donors, while for Libyan donors, Na-K (r = 0.680) and Fe-Mn (r = 0.624) correlations emerged as strongly significant. Only K was found to have a strong positive correlation (r = 0.611) with age for Pakistani donors while this correlation was significantly negative (r = -0.500) for Libyan donors, probably arising from individual food habits. Other metals showed no viable relationship with age. Principal Component Analysis (PCA) and Cluster Analysis (CA) of the data evidenced food, industrial emissions and automobile emissions as possible sources of metal distribution. The results of the present study are compared with those reported for subjects from other regions of the world.

Spatial variations in selected metal contents and particle size distribution in an urban and rural atmosphere of Islamabad, Pakistan

Spatial variations in total suspended particulate matter (TSP) were investigated for distribution of metals and particle size fractions in the urban and rural atmosphere of Islamabad, Pakistan. The metals Na, K, Fe, Mn, Pb, Cd, Cr, Zn, Ni and Co, and the particle fractions <2.5, 2.5-10, 10-100 and >100 microm were included in the study. TSP samples were trapped on glass fibre filters using high volume samplers and quantification of metals was done using Atomic Absorption Spectrometry employing HNO(3) based wet digestion. At the urban site, Na was dominant at 2.384 microg/m(3) followed by K, Fe and Zn with 0.778, 0.667 and 0.567 microg/m(3) as mean concentrations, respectively. The metal levels for the rural site ranged from 0.002 microg/m(3) for Cd to 1.077 microg/m(3) for Na. However, compared with the urban site, mean Pb concentration showed an almost two-fold enhancement, i.e., 0.163 Vs. 0.327 microg/m(3). Metals and particle size source identification was done using Principal Component Analysis and Cluster Analysis. Five sources were traced out for the urban site: industrial, soil, automobile emissions, metallurgical industries and excavation activities. For the rural site, four sources were recorded: agricultural, automotive emissions, excavation activities and metallurgical units. Collectively, for both the sites, PM(10-100) emerged as a major contributor to TSP, followed by PM(2.5-10), PM(<2.5) and PM(>100) in that order. The metals showed in general positive relationship with fine particulate fractions (PM(2.5-10), PM(<2.5)), and negative correlation with coarse fractions (PM(10-100), PM(>100)). Comparison with the corresponding data from various Asian sites revealed that the levels of Na, K, Fe, Mn, Co and Ni for the present study were lower than those reported for grossly polluted cities of the world.

Multivariate analysis of the selected metals in the hair of cerebral palsy patients versus controls

Seventeen metals were measured in scalp hair samples from cerebral palsy patients (CPPs) and controls. Samples were collected from 95 CPPs and 93 controls. The nitric acid-perchloric acid wet digestion procedure was used for quantification of the selected metals by flame atomic absorption spectrophotometry. The concentrations of Ag, Ca, Cd, Co, Cr, Li, and Mg were significantly higher and those of Cu, Fe, K, Mn, Na, Ni, Pb, and Sb were lower in the hair of CPPs compared with controls. Astrong positive correlation was found between Ca and Mg in the hair of controls but not in that of CPPs. Antimony was found significantly negative in terms of its correlation with Co and Cu in CPPs group but not in the controls. Principal component analysis (PCA) of the data extracted seven factors for CPPs and six factors for controls. Cluster analysis (CA) was also used to support the PCA results. The study evidenced some specific source of Mg and Sb in the hair of CPPs.

Multivariate analysis of selected metals in tannery effluents and related soil

Effluent and relevant soil samples from 38 tanning units housed in Kasur, Pakistan, were obtained for metal analysis by flame atomic absorption spectrophotometric method. The levels of 12 metals, Na, Ca, K, Mg, Fe, Mn, Cr, Co, Cd, Ni, Pb and Zn were determined in the two media. The data were evaluated towards metal distribution and metal-to-metal correlations. The study evidenced enhanced levels of Cr (391, 16.7 mg/L) and Na (25,519, 9369 mg/L) in tannery effluents and relevant soil samples, respectively. The effluent versus soil trace metal content relationship confirmed that the effluent Cr was strongly correlated with soil Cr. For metal source identification the techniques of principal component analysis, and cluster analysis were applied. The principal component analysis yielded two factors for effluents: factor 1 (49.6% variance) showed significant loading for Ca, Fe, Mn, Cr, Cd, Ni, Pb and Zn, referring to a tanning related source for these metals, and factor 2 (12.6% variance) with higher loadings of Na, K, Mg and Co, was associated with the processes during the skin/hide treatment. Similarly, two factors with a cumulative variance of 34.8% were obtained for soil samples: factor 1 manifested the contribution from Mg, Mn, Co, Cd, Ni and Pb, which though soil-based is basically effluent-derived, while factor 2 was found associated with Na, K, Ca, Cr and Zn which referred to a tannery-based source. The dendograms obtained from cluster analysis, also support the observed results. The study exhibits a gross pollution of soils with Cr at levels far exceeding the stipulated safe limit laid down for tannery effluents.

A comparative study based on gender and age dependence of selected metals in scalp hair

Levels of 10 metals (Ca, Mg, Fe, Zn, Cu, Mn, Cd, Co, Cr and Ni) in the scalp hair of male and female donors, with age groups between 3 and 100 years, were determined by ICP-AES. In total, 58 male and 30 female hair samples were analyzed in triplicate. The donors belonged to the rural area of district Chakwal, a well-known typical non-urban site in Pakistan. Calcium showed the highest concentration of 462 microg/g in the hair of males and 870 microg/g in those of females followed by Zn, at 208 and 251 microg/g for the two sexes. For male donors, Cd showed the lowest concentration (1.15 microg/g) while for female donors Co remained at minimum level (0.92 microg/g). The order of decreasing metal concentration in the hair of male donors was: Ca > Zn > Mg > Fe > Cu > Mn > Ni > Cr > Co > Cd while that for female donors it was: Ca > Zn > Mg > Fe > Cu > Mn > Cr > Ni > Cd > Co. The female group exhibited enhanced levels of all selected metals except Fe and Co in their hair as compared with the male counterparts. A strong bivariate positive correlation was found between Fe and Zn (r = 0.841) for the hair samples from male category while for the female category, strong positive correlations were observed between Ca-Mg (r = 0.617), Ca-Zn (r = 0.569), Ca-Mn (r = 0.565), Mg-Mn (r = 0.655), Cr-Cu (r = 0.655) and Cr-Ni (r = 0.685). The distribution of metals in the hair of donors with respect to different age groups was also investigated for both genders. The study showed that in case of males, the concentration of all selected metals decreased with increasing age except for Cu, Co and Cr. However, for females the hair metal levels increased with age, except for Co for which the concentration decreased with age. No appreciable change in the metal concentration was observed as a function of age for the combined sexes.

Profile of malignancies at Medical College, Ambajogai--(15 years retrospective study)

Present study comprises of a preliminary analysis of malignant lesions, diagnosed and confirmed by histopathological examination, carried out in Department of Pathology, S. R. T. R. Medical College, Ambajogai, from August 1976 to July 1991. 30,168 specimens were received for histopathological examination out of which 2,663 cases were diagnosed as malignant lesions (8.82%). 163 cases of leukemias were diagnosed by peripheral smear and bone marrow examination. Our of 2826 patients with malignant lesions 1,566 (55.41%) were males and 1,260 (44.59%) were females with M:F ratio as 1.24:1. Analysis of all malignant lesions showed more predilection towards genital organs (26.22%), gastrointestinal tract (13.72%) and breast (10.47%). Penis (11.36%), gastrointestinal tract (16.73%), oral cavity and tongue with pharynx (20.81%) and skin (11.11%) were leading sites in males where as cervix (30.63%) breast (22.46%), gastrointestinal tract (10.00%), skin (6.82%) and lymphoma, leukaemias (7.30%) were common sites for malignancies in females. The higher incidence of genital and skin tumours is discussed in the paper. Available data is compared with data from Tata Memorial Cancer Hospital Bombay and Cancer Hospital at Barshi in Solapur District of Maharashtra.

Physiological pharmacokinetic and pharmacodynamic model of physostigmine in the rat

A physiological model for physostigmine disposition was developed in the rat which incorporated anatomical, physiological, and biochemical parameters, i.e. tissue volume, plasma flow rates, drug metabolism, and tissue-to-plasma partition coefficients. Predicted concentrations of physostigmine in different tissue compartments were consistent with the experimental observations in the rat following an iv dose. Part of this study also compared the time course changes in measured effect, as percentage change in cholinesterase activity in brain, and related these changes to the plasma or brain drug level in either a combined pharmacokinetic-pharmacodynamic (plasma physostigmine-effect relationship) or a dynamic model (brain physostigmine-effect relationship). Fitting the time course of the effect in a pharmacokinetic-pharmacodynamic model required an effect compartment with the equilibration rate constant between it and the plasma compartment. Both models help to understand whether the cholinesterase activity is homogeneous or heterogenous in the brain.

Pharmacokinetics and pharmacodynamics of physostigmine in the rat after intravenous administration

The time course of physostigmine (Phy) and metabolites in plasma, brain, and muscle, the inhibition of butyrylcholinesterase (BuChE) in plasma, and cholinesterase (ChE) activity in brain and muscle were studied in rat after iv bolus administration of 3H-Phy (100 micrograms/kg). The semilogarithmic plot of plasma Phy concentration versus time indicates a biphasic decline. These data were analyzed by nonlinear computer fitting program (PC-NONLIN) using a two-compartment open model with bolus input and first order elimination. The pharmacokinetic constants A, B, alpha, beta, AUC, K10 half-life, alpha-half-life, beta-half-life, K10, K12, and K21 were obtained. The alpha-half-life and the beta-half-life were 1.31 and 15.01 min, respectively. The apparent volume of distribution was found to be 270 ml. The clearance was 12.43 ml min-1. The half-life of Phy in brain was 11 min. The brain to plasma ratio (1.69) peaked at 15 min. Phy is metabolized to eseroline and three other metabolites, M1, M2, and M3. The distribution studies showed that the radioactivity per g of tissue was highest in kidney and liver, whereas the percentage of the administered dose in terms of radioactivity was maximum in muscle followed by liver. The maximum inhibition of BuChE (52%) correlates with the highest Phy concentration (84.6 ng/ml) in plasma at 2 min and 70% of the enzymic activity recovered by 45 min. The maximum inhibition of ChE (63%) in the brain correlates with the highest Phy concentration (128 ng/g) at 3 min, and 85% of the enzymic activity was recovered within an hour.(ABSTRACT TRUNCATED AT 250 WORDS)

The adrenal and renal veins of man and their connections with azygos and lumbar veins

There exist many variations in the manner of formation, dimensions and place of termination of the central adrenal veins. In addition, some superficial adrenal veins may be substantial in size and may themselves drain directly into the renal veins and/or into other vessels which communicate with azygos and lumbar veins. This provides a route for venous adrenal blood to the heart via the azygos system and the superior vena cava rather than via the inferior vena cava. Variations in the formation and disposition of the renal veins are also described and the patterns of communication between somatic veins (including veins of the azygos and lumbar systems) and the left renal vein are illustrated and discussed in relation to the findings of others.

Variations in the composition of the human rectus sheath: a study of the anterior abdominal wall

Three modes of construction of the rectus sheath above the arcuate line were found in a study of 40 cadavers. The classical description occurred most frequently, in 24 cases. The other constructions conformed to those described in earlier studies although the incidences were different. The accessory internal oblique muscle was found in none of the 40 cadavers, and pyramidalis muscle occurred on one or both both sides in only 3 out of 56 specimens. The shape and position of the arcuate line were neither symmetrical nor constant, and neither was the arrangement of the nerve supply to the rectus abdominis muscle or to the overlying skin.

Distribution and pharmacokinetics of physostigmine in rat after intramuscular administration

The distribution and pharmacokinetics of [3H]physostigmine (Phy) and the relationship between the time course of Phy concentration and butyrylcholinesterase (BuChE) inhibition in plasma was studied in rat after im administration (650 micrograms/kg). The concentrations of Phy and its metabolites were determined in plasma and brain by high-performance liquid chromatography and by counting the radioactivity in the chromatographic fractions. The half-life of Phy in plasma and brain was 17 and 16 min, respectively. The brain-to-plasma ratio of Phy peaked (1.61) at 22 min. The time course of Phy and its metabolites (eseroline, M1 and M2) indicated that Phy was rapidly metabolized and M1 appeared to be the major metabolite. The distribution studies showed that the concentration of radioactivity per gram of tissue was higher in kidney and liver than the other tissues. The time course of BuChE activity and plasma Phy concentration showed that the maximum enzymatic inhibition (47%) occurred at about the same time (7 min) as the peak plasma concentration (583 ng/ml at 5 min). The enzymatic activity recovered to 81% at 2 hr and 100% within 24 hr.

Determination of physostigmine in plasma and brain by HPLC

A specific, reliable, and accurate high performance liquid chromatographic method is described for the determination of physostigmine in plasma and brain using carbaryl as an internal standard. Plasma and brain containing physostigmine were first precipitated with TCA, and then carbaryl was added. This was followed by chloroform extraction and then evaporation. The residue was reconstituted in the mobile phase. Physostigmine, its hydrolyzed product eseroline, and carbaryl were separated on a reversed-phase column eluted with mobile phase containing octanesulfonic acid with phosphate buffer in a methanol and water solution. The eluted compounds were detected at 245 nm, and physostigmine was quantified from the ratio of the area of physostigmine to carbaryl peaks. The chromatography was complete within 15 min. The dynamic range of quantitation of physostigmine was 0.05 micrograms to 0.5 micrograms/mL plasma or per gram of brain. Analytical recoveries varied from 95 to 107% over this range. Coefficient of variation ranged from 1.7 to 9.5%. This method was applied to study plasma and brain concentration in rats after 650 micrograms/kg intramuscular administration of physostigmine. The ratio of brain to plasma was found to be 0.48 and 1.97 at 15 and 30 min, respectively.

Metabolism of 2,4-dichlorophenol by isolated perfused rat liver

The uptake and metabolism of 2,4-[14C]dichlorophenol (2,4-[14C]DCP) was studied in the isolated perfused rat liver. The uptake of radioactivity in liver increased 6.6% (25.3-31.9%) in the presence of adenosine 5'-triphosphate (ATP) and 14.9% (25.3-40.2%) in the presence of ATP and galactosamine. This increase in the uptake of radioactivity was indicative of maintaining the integrity of liver cells. The glucuronide conjugate of 2,4-DCP in bile was derivatized by permethylation and characterized by gas chromatography-mass spectrometry (GC-MS). Two unusual metabolites were isolated from the liver and perfusate by extracting with hexane. The gas chromatogram of these metabolites gave peaks at retention times 12.0 and 15.5 min, and were characterized by mass spectrometry. The fragmentation pattern of these metabolites confirmed their identity as dichloromethoxyphenols.

Distribution and metabolism of 2,4-dichlorophenol in rats

The metabolism and distribution of 2,4-dichlorophenol (2,4-DCP) were studied in the rat after intravenous administration of 10 mg/kg. 2,4-DCP was determined by gas chromatography with an electron-capture detector. The highest concentration of 2,4-DCP was found in kidney, followed by liver, fat, and brain. 2,4-DCP is metabolized to glucuronide and other conjugates. The parent compound and its conjugates were rapidly eliminated from the body. The half-lives of 2,4-DCP and its conjugates in plasma, fat, brain, liver, and kidney ranged from 4 to 30 min. The volume of distribution of 2,4-DCP in plasma was 3.7 l/kg. Tissue/plasma ratios indicated that 2,4-DCP has a greater affinity for kidney.