Antipsoriatic potential of Annona squamosa seed oil: An in vitro and in vivo evaluation

BACKGROUND

Corticosteroids remains compound of choice for topical treatment of psoriasis. Several side effects associated with chronic application of corticosteroids limit its uses. Hence, there is a need to find a safe and effective alternative agent for psoriasis treatment.

PURPOSE

The study aimed to investigate the in vitro and in vivo efficacy of petroleum ether extract of Annona squamosa seeds (ASO) as an antipsoriatic agent. The toxicity profile of ASO and its effect on psoriasis-induced inflammation has also been determined.

METHODS

Physicochemical characterization was performed to determine constituents of ASO. Anti-proliferative activity of ASO was studied by Sulforhodamine B (SRB) assay using HaCaT cell lines. Oxazolone-induced psoriasis in female Balb/C mice was used as an animal model for investigating in vivoefficacy of ASO. Inflammatory markers were analyzed by immunohistochemical staining of mice ears. Safety profile of ASO was confirmed by performing acute dose dermal toxicity and repeated dose dermal toxicity testing.

RESULTS

Predominant presence of polyunsaturated fatty acids viz. linoleic acid and oleic acid in ASO was confirmed by ¹H NMR, ¹³C NMR and GC-MS analysis. The petroleum ether extract of Annona squamosa seeds showed inhibition of cell proliferation of keratinocytes (HaCaT cells). The growth inhibitory property of ASO was significantly higher than that was observed in presence of corticosteroid, clobetasol propionaste (CP). Application of ASO to the ears of Balb/C mice with oxazolone induced psoriasis showed marked reduction in erythema and edema, which was comparable to treatment with 0.05% CP cream. The increased levels of cytokines IL6, IL17, TNF-α, INF-γ, GMCSF, and infiltration of CD4 T cells observed in psoriasis lesions were decreased upon application of ASO. Acute and repeated dermal toxicity studies of ASO did not reveal any adverse events affirming the safety of ASO.

CONCLUSION

The present data has demonstrated that ASO is a safe and effective anti-psoriatic agent when tested in animal models. The efficacy of ASO in preclinical studies could further be exploited for the development of potential novel topical antipsoriatic agent for therapy in humans.

Antitumor activity of Annona squamosa seed oil

CONTEXT

Custard apple (Annona squamosa Linn.) is an edible tropical fruit, and its seeds have been used to treat "malignant sore" (cancer) and other usage as insecticide. A comparison of extraction processes, chemical composition analysis and antitumor activity of A. squamosa seed oil (ASO) were investigated.

MATERIALS AND METHODS

The optimal extraction parameters of ASO were established by comparing percolation, soxhlet, ultrasonic and SFE-CO₂ extraction methods. The chemical composition of fatty acid and content of total annonaceous acetogenins (ACGs) of ASO was investigated by GC-MS and colorimetric assay, and anti-tumor activity of ASO was tested using H₂₂ xenografts bearing mice.

RESULTS

The optimal extraction parameters of ASO were obtained as follows: using soxhlet extraction method with extraction solvent of petroleum ether, temperature of 80°C, and extraction time of 90min. Under these conditions, the yield of ASO was 22.65%. GC-MS analysis results showed that the main chemical compositions of fatty acid of ASO were palmitic acid (9.92%), linoleic acid (20.49%), oleic acid (56.50%) and stearic acid (9.14%). The total ACGs content in ASO was 41.00mg/g. ASO inhibited the growth of H₂₂ tumor cells in mice with a maximum inhibitory rate of 53.54% by oral administration. Furthermore, it was found that ASO exerted an antitumor effect via decreasing interleukin-6 (IL-6), janus kinase (Jak) and phosphorylated signal transducers and activators of transcription (p-Stat3) expression.

DISCUSSION AND CONCLUSION

The results demonstrated that ASO suppressed the H₂₂ solid tumor development may due to its main chemical constituents unsaturated fatty acid and ACGs via IL-6/Jak/Stat3 pathway. ASO may be a potential candidate for the treatment of cancer.

Cyclopeptides with anti-inflammatory activity from seeds of Annona montana

Four new cyclopeptides, cyclomontanins A-D (1- 4), annomuricatin C (5), and (+)-corytuberine were isolated from a methanol extract of Annona montana seeds. Their structures were elucidated by 2D NMR analysis, ESIMS/MS fragment evidence, and chemical means. The structure of 1 was confirmed by synthesis. Compounds 1, 3, and 4 exhibited anti-inflammatory activity in vitro using the J774.1 macrophage model.

Annona squamosa seed extract in the regulation of hyperthyroidism and lipid-peroxidation in mice: possible involvement of quercetin

Annona squamosa (Custard apple) seeds are generally thrown away as waste materials. The extract of these seeds was evaluated for its possible ameliorative effect in the regulation of hyperthyroidism in mouse model. Serum triiodothyronine (T(3)), thyroxine (T(4)) concentrations, hepatic glucose-6-phospatase (G-6-Pase) and 5'-mono-deiodinase (5'DI) activity were considered as the end parameters of thyroid function. Simultaneously hepatic lipid peroxidation (LPO), superoxide dismutase (SOD) and catalase (CAT) activities were investigated to observe its hepatotoxic effect, if any. L-T(4) administration (0.5 mg/kg/d for 12 days, i.p.) increased the levels of serum T(3) and T(4), activity of hepatic G-6-Pase, 5'DI and LPO with a parallel decrease in SOD and CAT activities. However, simultaneous administration of the Annona seed extract (200 mg/kg) or quercetin (10 mg/kg) to T(4)-induced hyperthyroid animals for 10 days, reversed all these effects indicating their potential in the regulation of hyperthyroidism. Further, the seed extract did not increase, but decreased the hepatic LPO suggesting its safe and antiperoxidative nature. Quercetin also decreased hepatic LPO. When relative efficacy was compared with that of propyl thiouracil (PTU), a standard antithyroidic drug, experimental seed extract appeared to be more effective. Phytochemical analyses including HPLC revealed the presence of quercetin in the seed extract and the results on the effects of quercetin suggested the involvement of this phytochemical in the mediation of antithyroidal activity of Annona squamosa seed extract.

Germination ecophysiology of Annona crassiflora seeds

BACKGROUND AND AIMS

Little is known about environmental factors that break morphophysiological dormancy in seeds of the Annonaceae and the mechanisms involved. The aim of this study was to characterize the morphological and physiological components of dormancy of Annona crassiflora, a tree species native to the Cerrado of Brazil, in an ecophysiological context.

METHODS

Morphological and biochemical characteristics of both embryo and endosperm were monitored during dormancy break and germination at field conditions. Seeds were buried in the field and exhumed monthly for 2 years. Germination, embryo length and endosperm digestion, with endo-beta-mannanase activity as a marker, were measured in exhumed seeds, and scanning electron microscopy was used to detect cell division. The effect of constant low and high temperatures and exogenous gibberellins on dormancy break and germination was also tested under laboratory conditions.

KEY RESULTS

After burial in April, A. crassiflora seeds lost their physiological dormancy in the winter months with lowest monthly average minimum temperatures (May-August) prior to the first rainfall of the wet season. The loss of physiological dormancy enabled initiation of embryo growth within the seed during the first 2 months of the rainy season (September-October), resulting in a germination peak in November. Embryo growth occurred mainly through cell expansion but some dividing cells were also observed. Endosperm digestion started at the micropylar side around the embryo and diffused to the rest of the endosperm. Exogenous gibberellins induced both embryo growth and endo-beta-mannanase activity in dormant seeds.

CONCLUSIONS

The physiological dormancy component is broken by low temperature and/or temperature fluctuations preceding the rainy season. Subsequent embryo growth and digestion of the endosperm are both likely to be controlled by gibberellins synthesized during the breaking of physiological dormancy. Radicle protrusion thus occurred at the beginning of the rainy season, thereby maximizing the opportunity for seedlings to emerge and establish.