FISIOLOGIA DE HEMOSTASIA (COAGULACION)

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La marihuana puede resultar beneficiosa en el tratamiento de las enfermedades autoinmunitarias

La marihuana se usa actualmente para fines médicos, entre otros, para aliviar los efectos secundarios de la quimioterapia y tratar el dolor crónico. El "Journal of Biological Chemistry" informó de que científicos estadounidenses han encontrado ahora una posible aplicación nueva: el tratamiento de las enfermedades autoinmunitarias.

Científicos de la Universidad de Carolina del Sur (Columbia) investigaron si el tetrahidrocannabinol (THC) presente en la marihuana es capaz o no de alterar la expresión del ADN a través de vías epigenéticas. Al hacerlo, descubrieron que el THC afecta en realidad a un grupo de moléculas denominadas histonas. El sistema inmunitario, por tanto, queda suprimido.

Normalmente, la supresión del beneficioso sistema inmunitario es una de las consecuencias negativas del uso de la marihuana. Pero en las enfermedades autoinmunitarias, como la artritis, el lupus o la esclerosis múltiple, en las que la inflamación crónica desempeña un papel fundamental, el uso de la marihuana podría ser efectivo, sugieren los investigadores

Tomado de Univadis.com

• Xiaoming Yang, 
• Venkatesh L. Hegde, 
• Roshni Rao, 
• Jiajia Zhang,
• Prakash S. Nagarkatti, 
• and Mitzi Nagarkatti 

Histone modifications are associated with Delta(9)-tetrahydrocannabinol-mediated alterations in antigen-specific T cell responses. J. Biol. Chem. jbc.M113.545210. First Published on May 19, 2014,doi:10.1074/jbc.M113.545210

Cannabis can disrupt fertility in men

Men who take cannabis regularly could impair their ability to father a child. According to a British study published in "Human Reproduction", cannabis changes the shape and size of sperm.

For the study, scientists from the universities of Sheffield and Manchester recruited over 2,200 men from 14 fertility clinics in Great Britain and asked them to complete detailed questionnaires about their lifestyle and medical history. Data on sperm morphology was available from 1,970 men. In 318 of them, less than four per cent of the sperm was of normal size and shape. These men were compared to the other 1,652 people.

The researchers found that men with less than four per cent of "normal" sperm, were nearly twice as likely to have produced the sperm samples during the summer months (June to August), or, if they were younger than 30 years of age, they had used cannabis during the previous three months. However, the morphology of the sperm was better when the subjects had been sexually inactive for more than six days.

Other lifestyle factors such as smoking or drinking did not affect shape and size of the sperm. However, effects on the DNA of the sperm could not be entirely ruled out.

Men with poor sperm morphology were frequently looking for possible factors in their lifestyles that could be causing this, said study author Allan Pacey. "It is therefore reassuring to find that there are very few identifiable risks." He advised cannabis users to stop using the drug if they want to father a child.

Tomado: Univadis.com

Ref:  A: Pacey y cols.  Modifiable and non-modifiable risk factors for poor sperm morphology. Hum. Reprod. (2014)