Detection of zoonotic-borne parasites in Rattus spp. in Klang Valley, Malaysia.

Background and Aim: Rattus spp. are the most common animals capable of adapting to their environment. They can be reservoirs or vectors of diseases that facilitate the transmission of zoonotic-borne parasites to humans. Hence, a study on the detection of parasites in rat populations in urban areas is crucial to prepare for emerging zoonosis. Therefore, this study aims to identify blood parasites, ectoparasites, and helminths in Rattus spp. from wet markets located in Klang Valley, an urban area with a high-density human population. Materials and Methods: A total of 32 rats were trapped in several wet markets in Klang Valley, Malaysia. They were anesthetized for morphometric examination followed by exsanguination. Various parasitological techniques such as perianal tape test, simple flotation, direct examination of the intestine, and fecal smear were performed for intestinal parasite detection; hair plucking, skin scraping, and full body combing for ectoparasite identification; and blood smear, microhematocrit centrifugation, and buffy coat techniques for blood parasite detection. Results: The rats were identified as Rattus rattus (71.9%) and Rattus norvegicus (28.1%). The only blood protozoan found was Trypanosoma lewisi. The ectoparasites identified belonged to two broad groups, mites (Laelaps spp. and Ornithonyssus spp.) and fleas (Xenopsylla cheopis), known to be parasitic zoonotic disease vectors. The zoonotic intestinal parasites were cestodes (Hymenolepis nana), nematodes (Nippostrongylus brasiliensis, Strongyloides spp., Trichuris spp., Capillaria spp., and Syphacia spp.), and intestinal protozoa (coccidian oocysts and Giardia spp.). Microscopic images showing Giardia spp. are the first report of this organism in rats in Malaysia. Conclusion: Rats caught in this urban area of the Klang Valley harbor parasites can pose a potential zoonotic threat to humans, raising public health concerns because of their proximity to densely populated urban areas.

Prophylactic effect of edible bird's nest on acetaminophen-induced liver injury response in mice model.

Edible bird's nest (EBN) is one of the natural products believed to pose health-enhancing properties. To provide a better insight into the protective role of EBN from a toxicological perspective, acetaminophen (APAP) as a common hepatotoxicant is chosen. This study focuses on the regenerative response of prophylaxis EBN extract in APAP-induced liver injury (AILI) of mice model. Eighty (80) ICR mice were assigned to groups of control, APAP (500 mg/kg), silymarin (200 mg/kg), and prophylactic EBN (60, 120 and 250mg/kg). The EBN and silymarin were orally administered daily for 7 days followed by an APAP intraperitoneal induction. Animals were sacrificed at 5, 10 and 24 hours post-APAP dosing (hpd). Liver samples were processed for hematoxylin and eosin (H&E) staining and proliferating cell nuclear antigen (PCNA) immunostaining. Significant differences in histological changes between APAP and prophylactic EBN groups were observed at 10 hpd with complete liver recovery for all groups at 24 hpd except for EBN 250 that continuously showed injuries. Hepatocyte proliferation was initiated at 5 hpd in EBN 60 and 120, while at 24 hpd, EBN 120 and 250 expressed higher PCNA-stained hepatocytes. The hepatoprotective role of EBN was shown earlier in EBN 60 and 120, while cellular proliferation delay in EBN 250. In conclusion, EBN has the potential as a prophylactic liver supplement to accelerate hepatic regeneration in the AILI model.

Histopathological changes of acetaminophen-induced liver injury and subsequent liver regeneration in BALB/C and ICR mice.

BACKGROUND AND AIM: Laboratory mice are widely used as a research model to provide insights into toxicological studies of various xenobiotic. Acetaminophen (APAP) is an antipyretic and analgesic drug that is commonly known as paracetamol, an ideal hepatotoxicant to exhibit centrilobular necrosis in laboratory mice to resemble humans. However, assessment of histopathological changes between mouse strains is important to decide the optimal mouse model used in APAP toxicity study. Therefore, we aim to assess the histomorphological features of APAP-induced liver injury (AILI) in BALB/C and Institute of Cancer Research (ICR) mice. MATERIALS AND METHODS: Twenty-five ICR mice and 20 BALB/C mice were used where five animals as control and the rest were randomly divided into four time points at 5, 10, 24 and 48 hours post-dosing (hpd). They were induced with 500 mg/kg APAP intraperitoneally. Liver sections were processed for hematoxylin-eosin staining and histopathological changes were scored based on grading methods. RESULTS: Intense centrilobular damage was observed as early as 5 hpd in BALB/C as compared to ICR mice, which was observed at 10 hpd. The difference of liver injury between ICR and BALB/C mice is due to dissimilarity in the genetic line-up that related to different elimination pathways of APAP toxicity. However, at 24 hpd, the damage was markedly subsided and liver regeneration had taken place for both ICR and BALB/C groups with evidence of mitotic figures. This study showed that normal liver architecture was restored after the clearance of toxic insult. CONCLUSION: AILI was exhibited earlier in BALB/C than ICR mice but both underwent liver recovery at later time points.