Will Killer Peptide Offer New Therapy Against Swine Flu H1N1 Virus?

The 2009 swine flu outbreak in humans is caused by a new strain of influenza A virus subtype H1N1. The origin of this new strain is unknown, and the World Organization for Animal Health (OIE) reports that this strain has not been isolated in pigs.

This is a version of swine flu hemagglutinin amino acid sequence:

MKAILVVMLYTFATANADTLCIGYHANNSTDTVDTVLEKNVTVTHSVNLLEDKHNGKLCK

LRGVAPLHLGKCNIAGWILGNPECESLSTASSWSYIVETSSSDNGTCYPGDFIDYEELRE

QLSSVSSFERFEIFPKTSSWPNHDSNKGVTAACPHAGAKSFYKNLIWLVKKGNSYPKLSK

SYINDKGKEVLVLWGIHHPSTSADQQSLYQNADAYVFVGSSRYSKKFKPEIAIRPKVRDQ

EGRMNYYWTLVEPGDKITFEATGNLVVPRYAFAMERNAGSGIIISDTPVHDCNTTCQTPK

GAINTSLPFQNIHPITIGKCPKYVKSTKLRLATGLRNVPSIQSRGLFGAIAGFIEGGWTG

MVDGWYGYHHQNEQGSGYAADLKSTQNAIDEITNKVNSVIEKMNTQFTAVGKEFNHLEKR

IENLNKKVDDGFLDIWTYNAELLVLLENERTLDYHDSNVKNLYEKVRSQLKNNAKEIGNG

CFEFYHKCDNTCMESVKNGTYDYPKYSEEAKLNREEIDGVKLESTRIYQILAIYSTVASS

LVLVVSLGAISFWMCSNGSLQCRICI

The H1N1 swine flu can be transmitted from human to human, and causes the normal symptoms of influenza, such as fever, coughing and headache. This has brought about new concerns of a pandemic outbreak. Although vaccination can be an effective strategy for preventing this virus, it will take at least a few months for the discovery and development of antiviral drugs.

A killer decapeptide (KP) against influenza A virus and the mechanisms of actions were described by researchers. This killer decapeptide represents the functional internal image of a yeast (Pichia anomala) killer toxin that has antimicrobial and anti-human immunodeficiency virus type 1 (HIV-1) activities. After treating with a KP concentration of 4 ug/ml, the scientists observed the complete inhibition of virus particle production and a marked reduction of the synthesis of viral proteins (membrane protein and hemagglutinin, in particular).Moreover, mice infected with influenza A/NWS/33 (H1N1) virus were inoculated with KP (100 ug/mice) once a day for ten days resulting in an improved survival rate of 40% and significantly decreased viral levels in their lungs.

Will this be a suggestion for treatment of H1N1 Swine Flu? It needs further study from scientist. The KP is anti-idiotypic antibody (KT-scFv) -derived peptide. Killer decapeptide exerted a strong fungicidal activity against Candida albicans, which was attributed to peptide interaction with beta-glucan. As this polysaccharide is also a critical component of the cryptococcal cell wall, it was found to have inhibitory activity and that has a potential therapeutic effect against pathogenic microorganisms, HIV-1, and influenza A virus by different mechanisms of action.

The synthetic peptides have been widely used for therapeutic peptide research. A synthetic peptide antigen corresponding to a region of the glycoprotein gp41 encoded by the env gene of HIV-2 is found to be immunologically reactive with HIV-2 specific antibodies. This is useful in assays for detection of HIV-2 infection or exposure and in compositions to elicit the production of antibodies against HIV-2 in animals including man.

The specificity of peptides has tremendous clinical value and makes them very attractive therapeutics. More than 40 peptides are in the world market and about 270 peptides are in the clinical phase.In addition, more than 400 are in advanced preclinical phases worldwide. These trends suggest that the therapeutic peptide represents a novel therapeutic strategy in the clinical setting. The scientists will find out answer for this question soon: Will Killer Peptide Offer New Therapy Against Swine Flu H1N1 Virus?

Reference:

G. Conti, W. Magliani, S. Conti, L. Nencioni, R. Sgarbanti, A.T. Palamara, L. Polonelli. Therapeutic activity of an anti-idiotypic antibody-derived killer peptide against influenza A virus experimental infection. Antimicrobial Agents and Chemotherapy, 52. 12: 4331-4337

Peptides Could Help Control Obesity!

The treatment of obesity has not been proven by any single agent to reduce the body weight for more than 5-10%. Researchers found that single molecules can be designed that are capable of simultaneously activating more than one mechanism to safely normalize body weight.

Glucagon and GLP-1 are peptide hormones best known for their insulin and glucose counter-regulatory actions. Scientists generated a set of high-potency glucagon-based co-agonist peptides. After weekly administration of the PEGylated peptides, it was found that those peptides were highly effective in lowering adiposity and improving glucose tolerance of diet induced obese mice. The peptide with balanced co-agonism proved especially efficacious, and within only a few weeks of therapy there was an apparent normalization of body weight and blood glucose.

Reference:

Day JW, etc. A new glucagon and GLP-1 co-agonist eliminates obesity in rodents. Nat Chem Biol. 2009 Oct;5(10):749-57. Epub 2009 Jul 13.