Table 3.

Therapeutic potential of Punica granatum on the respiratory system

Model	Activity	Plant part/Compd.	Study design	Mechanism	Ref.
Simulation	Antiviral activity against SARS-Cov-2	PPE; Punicalagin; Punicalin; Urolithin A	Molecular docking simulation through Yasara Structure software based on the AutoDockLGA algorithm and AMBER03 force field; Molecular dynamics simulation in LARMD server	↓SARS-CoV-2 S-glycoprotein binding ability to ACE2 receptor PPE MIC= 0.06 mg/ml Punicalin MIC= 0.14 mg/ml	(102)
Bacterial	Antimicrobial activity against Mycobacterium tuberculosis and b-lactamase-producing Klebsiella pneumoniae	Fruit compounds: caffeic acid and ellagic acid; EGCG and quercetin	Double-disc synergy; Phenotypic confirmatory test for ESBL detection; Modified Hodge test	PPE: antimycobacterial activity; MIC 64–1024 mg/ml	(103)
				PJ: antimycobacterial activity; MIC 256 -41024 mg/ml
				EGCG and quercetin: antitubercular and antibacterial; MIC 32–256 mg/ml; MIC 64–56 mg/ml
				Caffeic acid and ellagic acid: antitubercular and antibacterial activity; MIC 64–512 mg/ml
Viral	Antiviral activities against human respiratory syncytial virus (RSV)	Fruit cortex (aqueous extract)	Cytopathic effect reduction assay	Anti-RSV activity IC50= 62.5 µg/ml	(104)
Viral	Antiviral activity against SARS-Cov-2	PPE	ABTS assay for antioxidant effects; SARS-CoV2 inhibitor screening assay kit; Three extract concentrations ranging from 0.04 mg/ml to 1 mg/ml; 3CL protease assay (0.04 and 0.2 mg/ml)	↓SARS-CoV-2 S-glycoprotein binding ability to ACE2 receptor and Activity of the virus 3CL protease	(20)
Viral	Antiviral activity against SARS-Cov-2	Punicalagin	3CL protease assay kit (BPS Bioscience)	↓Activity of the virus 3CL protease; IC50= 6.192 μg/ml	(105)
Cellular	Reduction in lung inflammation	PPE (Aqueous extract)	In vitro: human neutrophils	↓LPS-induced lung inflammation and myeloperoxidase activity	(106)
Cellular	Non-small cell lung carcinoma treatment	Leaves extract	Non-small cell lung carcinoma cell line A549, H1299 and mouse Lewis lung carcinoma cell line LL/2; Cell viability and colony formation assay; Wound-healing migration assay; Cell cycle and apoptosis analysis by flow cytometry; Mitochondrial membrane potential (∆Ym) assay; Detection of ROS	Arresting cell cycle progression in G2/M; Blocked H1299 cell migration and invasion; ↓Metalloproteinase 2 and 9 expressions, ROS and ∆Ym; IC50= 47 μg/ml	(107)
Cellular	Induced cell cycle arrest and apoptosis in human lung Adeno carcinoma A549 Cells	PJ	A549 cells treated with PJ (2% (v/v)) at several time exposures (0–72 hr); Quantification of apoptosis by Annexing V Labeling; Caspase-3, -8 and -9 analyses; MMP analyses	Induced cell cycle arrest at G0/G1 and apoptosis through intrinsic pathway; Loss of MMP; Release of cytochrome c in the cytosol; Activation of caspase-3 and -9	(108)
Cellular	Suppress microsomal prostaglandin E synthase-1 expression and induce apoptosis lung cancer	Ellagitannins; Leaves extract	A549 cells were incubated either with or without 10 ng/ ml IL-1β; 10 μM granatin A, granatin B, or geraniin for 24 hr; Enzyme immunoassay; TUNEL assay	↓mPGES-1 expression without affecting COX-2, TNF-α, inducible nitric oxide synthase, anti-apoptotic factor; B-cell chronic lymphocytic leukemia/lymphoma 2	(43)
Cellular	Anticancer activity	Fruit extracts of immature pomegranate	Human lung H1299 adenocarcinoma cells; 100 μg/ml of extracts from different fruit matrices	Induction of caspase-3 activity	(109)
Animal	Reduction in lung inflammation	PPE (Aqueous extract)	Male BalbC mice; intraperitoneal injection of 200 mg/kg extract; LPS-induced lung inflammation (5 µg intratracheal LPS instillation)	↓LPS-induced lung inflammation and myeloperoxidase activity	(106)
Animal	Alleviating asthma	Leaves (ethanol extract/microencapsulated extract)	Female BALB/c mice; Ovalbumin-induced asthma; Encapsulated extract (10 mg/ml, 25 µl per nostril)/ non-encapsulated pomegranate extract (20 mg/Kg, 25 µl per nostril); Intranasal instillation; Standard=dexamethasone	↓Leukocytes' (eosinophils) recruitment to bronchoalveolar fluid, IL-1β, and IL-5 in the lungs	(110)
Animal	Bronchospasmolytic effects	PPE (Aqueous extracts)	Isolated guinea pig trachea chains; Contractions induced by acetylcholine or histamine; 10 mg/ml plant extract	↓Force of contraction by histamine by 30-70%	(111)
Animal	Protection against acute lung injury	Alloyl-hexahydroxydiphenoyl (HHDP)-glucose (isolated from leaves)	Male BALB/c mice; intra-tracheal lipopolysaccharide (LPS)-induced acute lung injury; galloyl-HHDP-glucose (5, 50, and 100 mg/Kg); standard= dexamethasone at 5 mg/Kg	↓TNF-α, IL-6, and IL-1β gene expression and protein levels, lung inflammation, and cell accumulation	(112)
Animal	Protection against acute lung injury	Punicalagin	RAW 264.7 murine macrophage cell line; Immunocytochemical analysis	↓TNF-α, IL-1β, IL-6, protein concentration and myeloperoxidase activity; Suppressing p38 MAPKs and NF-κB pathways	(113)
Animal	Protection against acute lung injury	Punicalagin	Male BALB/c mice with acute respiratory distress syndrome induced by intranasal instillation of LPS (20 mg/kg); Treated with punicalagin (12.5, 25, and 50 mg/kg) 1 hr prior to LPS exposure; Control=dexamethasone (5 mg/kg)	↓TNF-α, IL-1β, IL-6, macrophage and neutrophil infiltration, myeloperoxidase activity, TLR4 expression and NF-κB activation pathways	(114)

¹ Pomegranate peel extract; ² Epigallocatechin Gallate; ³ Pomegranate juice