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Pathological evaluation of Polystichum squarrosum (D. Don) fern in laboratory rats
1Division of Pathology, Indian Veterinary Research Institute, Izatnagar, India.
Abstract:
Polystichum squarrosum fern fed (30% w/w) rats showed moderate mortality, decrease in body weight, less body fat and splenomegaly. On post-mortem examination, significant gross lesions were not seen in sacrificed animals. Histopathologically, Polystichum fed rats showed dilated Virchow Robin's space in brain, mild to moderate vascular changes likeoedema, engorgement of blood vessels and haemorrhages in most of the visceral organs, interstitial pneumonia in lungs, focal necrosis and generalised vacuolative degenerative changes in liver, more haemosiderin deposition and presence of higher number of megakaryocytes in spleen, shrunken glomeruli, more peri-glomerular space and more number of glomeruli per microscopic field in kidneys, focal hyperplasia of urinary bladder and moderate to marked depletion of germinal epithelium and spermatids in seminiferous tubules of testes. Pathologically, progressive changes were observed only in liver, urinary bladder and testes on 180 days post feeding (DPF). One fern fed rat sacrificed on 135 DPF showed hepatic tumour which was diagnosed as hepatocellular carcinoma. The results showed that P. squarrosum produced almost comparable pathological changes/preneoplastic lesions as reported in bracken fern fed animals. Long term exposure studies (i.e. 2 yrs) are desired.
Insights
Feeding rats Polystichum squarrosum fern caused organ damage and tumors, similar to bracken fern effects. Further long-term studies are needed to confirm risks.
Area of Science:
- Toxicology
- Pathology
- Veterinary Medicine
Background:
- Ferns are common in many environments, and some species are known to be toxic.
- Polystichum squarrosum is a fern species whose toxicological profile is not well-established.
- Understanding the potential health impacts of fern consumption is crucial for animal and human health.
Purpose of the Study:
- To investigate the toxicological effects of Polystichum squarrosum fern consumption in rats.
- To identify pathological changes and potential preneoplastic lesions associated with fern ingestion.
- To compare the effects of P. squarrosum with known toxic ferns like bracken fern.
Main Methods:
- Rats were fed a diet containing 30% Polystichum squarrosum fern.
- Animals were monitored for mortality, body weight changes, and body fat.
- Post-mortem examinations, including gross pathology and histopathology, were performed on sacrificed animals.
- Specific attention was paid to organ systems including the brain, lungs, liver, spleen, kidneys, urinary bladder, and testes.
Main Results:
- Polystichum squarrosum fern ingestion led to moderate mortality, decreased body weight, reduced body fat, and splenomegaly in rats.
- Histopathological examination revealed widespread vascular changes, interstitial pneumonia, liver degeneration, altered spleen morphology, kidney damage, and testicular germinal epithelium depletion.
- Progressive pathological changes were noted in the liver, urinary bladder, and testes by 180 days post-feeding.
- One rat developed hepatocellular carcinoma, a significant finding indicating carcinogenic potential.
- The observed pathological changes were comparable to those reported for bracken fern.
Conclusions:
- Polystichum squarrosum fern exhibits significant toxicological effects in rats, including organ damage and potential carcinogenicity.
- The fern induces pathological changes similar to those caused by bracken fern.
- Long-term exposure studies (e.g., 2 years) are recommended to fully assess the chronic toxicity and carcinogenic potential of P. squarrosum.
