S. W. van der Merwe

The effect of Senecio latifolius a plant used as a South African traditional medicine, on a human hepatoma cell line.

A number of traditional remedies used in South Africa contain pyrrolizidine alkaloids, some of which are hepatotoxic. We investigated the effect on human HuH-7 cells of Senecio latifolius DC., a plant that is a component of some traditional remedies and which is known to contain toxic pyrrolizidine alkaloids. Cells were also treated with extracts of a standard pyrrolizidine, retrorsine. The changes in the gross morphology of the cells were studied using light microscopy after haematoxylin and eosin staining. The cytoskeleton was investigated using fluorescence-labelled anti-beta-tubulin antibody and the nuclear organisation was studied using fluorescence-labelled antinuclear antibodies. The plant extracts gave rise to dose-dependent gross morphological changes. At high doses, we observed necrosis and at lower doses, destruction of the cytoskeleton, nuclear fragmentation and apoptosis. Doses of less than the equivalent of 330 ng/ml retrorsine led to multinucleated cells with failure in spindle formation and clumping of nuclear chromatin. This latter finding suggests that chronic low-dose treatment with such traditional remedies could give rise to teratogenic and/or carcinogenic effects.

Guideline for the diagnosis and treatment of chronic pancreatitis

BACKGROUND Chronic pancreatitis (CP) is defined as a continuing inflammatory disease of the pancreas characterised by irreversible morphological changes, often associated with pain and with the loss of exocrine and/or endocrine function that may be clinically relevant. Alcohol is the predominant cause of CP in the western world and is particularly prevalent in South Africa, especially in the indigent patient. CP ranks high among intractable diseases of the gastrointestinal tract. The tendency for substance abuse in the alcohol-induced group poses major psychological and socio-economic problems. OBJECTIVE CP is a disease with significant clinical and pathological heterogeneity. Level 1 evidence to support definitive guidelines for diagnosis, medical management and interventional therapy is lacking. Despite this paucity of robust scientific evidence, it is important to provide some assistance based on the best available evidence as to the current standard of care for CP in the South African context; this will aid all involved in the management of the disease, and includes clinicians, health care managers and funders. SCOPE The guidelines were developed as recommendations addressing the diagnosis, medical management and interventions, both endoscopic and surgical, for the management of a very complex and heterogeneous disease of the pancreas. The recommendations are particularly relevant in the South African context where the predominant patho-aetiological agents are alcohol-associated with smoking. RECOMMENDATIONS The guidelines provide clear recommendations regarding the diagnostic modalities available, both imaging (which includes MRI and endoscopic ultrasound (EUS)) and pancreatic function tests. The section on medical management makes recommendations on the use of analgesics, enzyme replacement and other therapeutic options in the non-interventional management of the majority of patients with CP. The section on interventional procedures identifies the indications and options available for the interventional management of both uncomplicated and complicated CP. The role of endoscopic and surgical modalities is defined, but it is in this context especially that the best available evidence, combined with the experience of the group, influenced the recommendations put forward. Owing to the lack of evidence and the complexity of the disease, it is recommended that, where possible, CP is managed in the context of a multidisciplinary team. VALIDATION The guidelines are based on best practice principles determined by the available evidence and the opinions of the group, which comprised 7 medical and surgical gastroenterologists with significant experience in dealing with patients with chronic pancreatitis in the South African context. The group convened between May 2009 and August 2010 under the auspices of the Hepato-Pancreatico-Biliary Association of South Africa (HPBASA) and the South African Gastroenterology Society (SAGES), and the guidelines are the result of broad consensus within this group. The draft was presented to other experts in this field of endeavour to ensure broader participation and consensus. PLANS FOR GUIDELINE REVISION: HPBASA and SAGES will publish a revised modification of the recommendations when new levels 1 and 2 evidence data are published.

Molecular diagnosis of hereditary hemochromatosis: application of a newly-developed reverse-hybridization assay in the South African population.

A recently developed strip‐assay for hemochromatosis provides a rapid method for simultaneous detection of multiple mutations, which among others includes the HFE gene mutations V53M, V59M, H63D, H63H, S65C, Q127H, E168Q, and C282Y, previously detected in the general South African population using gel‐based mutation‐screening methods. The objective of the study was to determine the frequency of the relatively rare mutations in samples selected for altered iron parameters or a family history of hereditary hemochromatosis (HH) as part of the validation process of the assay for routine diagnostic purposes. The study population consisted of 451 individuals previously screened for mutations C282Y and H63D by restriction enzyme analysis in order to confirm or possibly exclude a diagnosis of HH. These individuals were subjected to mutation screening using the commercially available hemochromatosis strip‐assay. Previous positive results for mutations C282Y and H63D in 233 individuals confirmed the accuracy of the reverse‐hybridization assay. Mutation S65C was detected in 13 Caucasians, including three compound heterozygotes. These constituted 2% (13/600) of the chromosomes without mutations C282Y or H63D. The African‐specific HFE mutation V53M was detected in one out of 11 (9%) African subjects screened. Mutation E168Q was detected in a single Caucasian individual together with mutation H63D. Our data demonstrate the value of the strip‐based technology in providing a rapid and reliable comprehensive test for simultaneous analysis of multiple mutations.

Hepatic osteodystrophy in rats results mainly from portasystemic shunting

Background and aims: In chronic liver disease, bone disease frequently develops. The contributions of the different features of liver disease such as parenchymal inflammation, portal hypertension, and portasystemic shunting on bone metabolism have not been systematically studied. The aim of this study was to identify the features of liver disease contributing to bone disease using rat models. Methods: Parenchymal liver disease was induced by carbon tetrachloride administration, portal hypertension by partial portal vein ligation, and portasystemic shunting by end to side anastomosis of the portal vein to the inferior vena cava. Normal and sham operated surgical animals served as controls. Serum calcium, 25-hydroxy vitamin D (25-OH vit D), and osteocalcin levels, and urinary deoxypyridinoline excretion were analysed. Testosterone and oestradiol levels were determined in male and female rats, respectively. Interleukin 1, interleukin 6, and tumour necrosis factor α (TNF-α) were determined in serum. Bone density was measured in all groups and in addition, in the surgical groups, histomorphometry was performed on undecalcified specimens of the proximal tibia. The calcium content of the femurs, removed at termination and ashed, was determined. Results: Early parenchymal disease and portal hypertension did not affect bone metabolism or body mass. Portasystemic shunting increased bone resorption, decreased bone formation, bone density, and trabecular bone volume which were commensurate with a reduction in body mass. TNF-α levels were elevated and testosterone levels were low in male portasystemic shunted rats. Conclusions: Portasystemic shunting in the rat adversely affects bone metabolism as part of a generalised catabolic state where high TNF-α and low testosterone and 25-OH vit D levels may play a role.

The cytotoxic effects of a traditional Zulu remedy, impila (Callilepis laureola)

The traditional Zulu remedy impila (Callilepis laureola) can cause acute fatal hepatocellular necrosis, especially in children. We investigated the mechanism(s) of toxicity using HuH-7 hepatocytes. Impila tubers were extracted with boiling water and the aqueous extract was used at different concentrations to study the effects on the morphology of the cells. Flow cytometry and labelling with fluorescent antibodies to tubulin were also used. At high concentrations, necrosis occurred; however, at lower concentrations, the extracts gave rise to a variety of changes including hypercondensation of chromatin, multinucleate cells, nuclear fragmentation and apoptosis. In addition, we observed destruction of cytoplasmic tubulin. These findings give further insight into the mechanism of toxicity of herbal remedies containing atractyloside.

South African guideline for the management of chronic hepatitis B : 2013

Hepatitis B remains a significant yet preventable health issue in South Africa. The introduction of the hepatitis B vaccine into the country some 18 years ago has demonstrated benefit, but the exposure to, and prevalence of chronic HBsAg positivity remain unacceptably high. Those with chronic hepatitis B virus infection have an elevated risk of developing cirrhosis with end-stage liver disease and a markedly elevated risk of hepatocellular carcinoma, independent of the presence of cirrhosis. The challenge in South Africa remains prevention through the universal vaccination coverage of all children and the identification of those with chronic hepatitis B virus infection. Over the last decade our understanding of hepatitis B and its behaviour and natural history in those with chronic infection has significantly improved. This understanding is key to identifying those who warrant further evaluation and therapy. A number of global societies have updated their guidelines in recent years. This document draws on these guidelines and serves to contextualise, for South Africa, practice guidelines for the management of chronic hepatitis B.

A large-scale automated method for hepatocyte isolation: effects on proliferation in culture.

Large-scale sterile methods for isolating hepatocytes are desirable for the development of bioartificial liver support systems. In this study the traditional centrifuge method was compared with the use of a Baylor Rapid Autologous Transfusion (BRAT) machine for isolating large quantities of porcine hepatocytes. After isolating hepatocytes, the methods were evaluated in terms of cell viability and yield per liver, proliferation over 7 days, and the effects on the cell cycle using the trypan blue exclusion test, conventional phase-contrast light microscopy, the lactate to pyruvate ratio, the leakage of lactate dehydrogenase (LD) and aspartate aminotransferase (AST), lidocaine clearance, albumin production, and flow cytometry. With the centrifuge method the mean cell viability was 92.5%, while with the BRAT method the viability was 95.9%. The minimal cell yields with the BRAT procedure were 7.3 × 109 for 250-ml centrifuge bowls and 2.8 × 109 for 165-ml bowls, which compares well with that found by other authors. Because the same initial procedures were employed in both methods the total hepatocyte yield per liver was comparable. Flow cytometry confirmed that the proliferation of hepatocytes was facilitated by oxygenation during the isolation procedure. The recovery of hepatocytes in culture following isolation was similar after either method. Daily microscopic investigation indicated that cytoplasmic vacuolization and granularities were present after either procedure and these disappeared following 3–4 days of culturing. Flow cytometry indicated that the hepatocyte cell cycle was similar after either method; at 7 days the profile indicated that the cells were still proliferating. Trends in the lactate to pyruvate ratio and the leakage of LD and AST indicated that the functional polarity of hepatocytes was regained after approximately 3 days. Lidocaine clearance at 4 days indicated that the cytochrome P450 system was active, while significant albumin production was apparent at day 5. The benefit of using BRAT technology in hepatocyte isolation lies in guaranteed sterility, convenience, speed, and the ability to oxygenate media and cell suspensions during the procedure.

Preventing organ damage by genetic testing for hereditary haemochromatosis

Abstract The rapid discovery of several iron-related genes in the last 10 years has led to the development of cost-effective genetic assays for early diagnosis of hereditary haemochromatosis (HH). A genetic predisposition for this relatively common autosomal recessive disease has been identified in approximately 1 in 100 South Africans of European descent. If left untreated, this condition may lead to organ damage presenting as cirrhosis, liver cancer, diabetes, arthritis, impotence, sterility and/or cardiac disease. Due to the fact that serum iron parameters are frequently affected by factors such as liver disease and inflammation, direct mutation detection has become the method of choice for accurate diagnosis of inherited iron overload in patients with elevated iron stores. Haemochromatosis can be prevented by regular blood donation or phlebotomy and therefore detection of a genetic predisposition at an early age, before irreversible damage to cardiac, hepatic and endocrine tissue occurs, represents an important clinical goal.