Muévete, no te quedes sentado...

Un estudio.   realizado  en el  Karolinska Institutet demuestra, al parecer, que estar menos tiempo sentado es una  forma saludable de vida, que ayuda a envejecer mejor, y a alargar la vida, ya que aumenta la longitud de los telómeros.


Los telómeros están relacionados con el envejecimiento, serían  fragmentos de DNA no codificante  que estarían  en el extremo distal del cromosoma. Se acepta que los telómeros serían como una especie de relojes biológicos  que marcarían el ritmo de "desgaste" o envejecimiento de la célula y se ha especulado que su acortamiento disminuiría la longevidad, ya que la célula estaría más próxima a su cierre de ciclo vital.Este acortamiento de los telómeros haría que los cromosomas fueran más inestables y favorecería la aparición de neoplasias ( cánceres).
 Hay una enzima la telomerasa, sobre cuya actividad se han publicado multitud de artículos en relación con sus funciones en la especie humana.
Esta enzima  tendría una actividad de transcriptasa inversa, es decir,  puede sintetizar ADN a expensas de un molde de RNA, y estaría producida en las células germinales  y permitiría el alargamiento de los telómeros, es decir, simplificando mucho, alargar la "vida" de la célula. Pero, alto y contengan sus expectativas de hallar  una piedra filosofal que  aumente la esperanza de vida, esta telomerasa también estaría inducida en algunos cánceres.La telomerasa normalmente  se haya reprimida por  las células somáticas, por lo que se produciría un acortamiento de los telómeros después de cada  división de la célula.

 En los individuos "normales" se ha detectado una  disminución de la longitud de los telómeros conforme  la edad. Se sabe que el  numero de divisiones celulares  se correlacciona directamente  con la longitud telomérica inicial.Se ha calculado incluso  cual es la pérdida de pares de base al año, que sería de  media  9 pb/ año.( estaríamos hablando de tejido hematopoyético, el más estudiado  por los diferentes cánceres de las células de la sangre).
 Naturalmente hay muchas variaciones: casi 20.000 pb en las células germinales,  10.000 pares de bases en "jóvenes" y de 8000 a 9000 pb en "viejos".

 Ahora que ha desaparecido hace poco el actor Robin Williams, el protagonista de la película "El Hombre Bicentenario" ( basada en una obra de Isaac Asimov), con la pena que nos produce la desaparición del carismático actor, pues recordar lo terrible que era la película con un robotizado Williams en el papel de un personaje que no muere en 200 años y que  nos arroja una preocupante hipótesis de cómo sería la vida desde ese enfoque.

 Estoy envejeciendo y mi cuerpo se está deteriorando y al igual que el de ustedes, al final dejará de funcionar. Como robot, podría haber vivido siempre. Pero hoy les digo a ustedes, que prefiero morir como hombre que vivir toda la eternidad como máquina.

- ¿Por qué lo desea?

- Para que se me reconozca. Solo por quien soy y por lo que soy. Ni más, ni menos. No busco la aclamación ni la aprobación. Sino la simple verdad de dicho reconocimiento. Este ha sido el objetivo elemental de mi existencia y debo conseguirlo tanto si quiero vivir, como morir con dignidad.

- Señor Martín. Lo que está usted solicitando es tremendamente complejo y controvertido, no será una decisión fácil. Le pido que sea usted paciente, voy a necesitar cierto tiempo para tomar una determinación en esta comprometida y delicada materia.

- Entonces esperare su decisión, Sra. Presidenta. Gracias por su paciencia. Lo hemos intentado (a Portia). [Seca una lágrima de su ojo.]

En su lecho de muerte, con Portia a su lado, Andrew alcanza a ver la de decisión del Congreso Mundial en la televisión:

- Según el informe cedido por la compañia Northam Robotics, el robot, también conocido como Andrew Martín, fue activado a las 17 horas y 15 minutos del 3 de abril del año 2005. Dentro de unas horas tendrá 200 años (en este momento Andrew cierra sus ojos y muere sin poder oír lo demás). Lo que significa que a excepción de Matusalén y de otros personajes bíblicos, Andrew es el ser humano viviente más viejo en los anales de la historia. Pues por medio de esta proclamación: Doy validez a su matrimonio con Portia Charney y reconozco su humanidad.

Sangre como método de regeneración del natural proceso de envejecimiento.

No, no es una broma ni un chiste sobre vampiros. Las  supuestas propieades regenerativas de la sangre aparecen  hoy, es una noticia la da una publicación científica seria, .concretamente, ésta.

 Eso si, la sangre ha de ser  de gente joven.
Insisto: la noticia va en serio.

Young blood to be used in ultimate rejuvenation trial

• 20 August 2014 by Helen Thomson

In California, people with Alzheimer’s will be given transfusions of young blood to see if improves their cognition – there's good reason to hope it might

IT SOUNDS like the dark plot of a vampire movie. In October, people with Alzheimer's disease will be injected with the blood of young people in the hope that it will reverse some of the damage caused by the condition.

The scientists behind the experiment have evidence on their side. Work in animals has shown that a transfusion of young mouse blood can improve cognition and the health of several organs in older mice. It could even make those animals look younger. The ramifications for the cosmetics and pharmaceutical industries could be huge if the same thing happens in people.

Disregarding vampire legends, the idea of refreshing old blood with new harks back to the 1950s, when Clive McCay of Cornell University in Ithaca, New York, stitched together the circulatory systems of an old and young mouse – a technique called heterochronic parabiosis. He found that the cartilage of the old mice soon appeared younger than would be expected.

It wasn't until recently, however, that the mechanisms behind this experiment were more clearly understood. In 2005, Thomas Rando at Stanford University in California and his team found that young blood returned the liver and skeletal stem cells of old mice to a more youthful state during heterochronic parabiosis. The old mice were also able to repair injured muscles as well as young mice (Nature, doi.org/d4fkt5).

Spooky things seemed to happen in the opposite direction, too: young mice that received old blood appeared to age prematurely. In some cases, injured muscles did not heal as fast as would be expected.

Several other experiments have shown similar effects. In 2012, Amy Wagersat Harvard University showed that young blood can reverse heart decline in old mice. Her team paired healthy young mice with old mice that had cardiac hypertrophy – a condition which swells the size of their heart – and connected their circulatory systems. After four weeks, the old mouse's heart had shrunk to the same size as its younger partner. In this experiment, the young mouse was seemingly unaffected by the old blood, its heart not changing in size.

Once the researchers had ruled out the effect of reduced blood pressure on the older mice, they identified a protein in the blood plasma called growth differentiation factor 11 (GDF11) that appeared to fall with age. To see if it was linked to the rejuvenating effects, the team gave old mice with enlarged hearts daily injections of GDF11 for 30 days. Their hearts decreased in size almost as much as they had in the parabiosis experiments (Cell, doi.org/q2f).

A year later, the same team showed in mice that daily injections of GDF11 also increases the number of blood vessels and the number of stem cells in the brain – both factors known to improve brain function. A separate team led by Tony Wyss-Coray at Stanford performed similar experiments. His team injected blood plasma from young mice into old mice and showed animprovement in the old mice's physical endurance and cognitive function(Nature Medicine, DOI: 10.1038/nm.3569).

In both mice and humans, GDF11 falls with age. We don't know why it declines, but we know it is involved in several mechanisms that control growth. It is also thought to mediate some age-related effects on the brain, in part by activation of another protein that is involved in neuronal growth and long-term memory.

So the billion-dollar question is: would a GDF11 boost have the same effect in humans? Wyss-Coray thinks it will, having taken the next step of injecting young human blood plasma into old mice. His preliminary results suggest that human blood has similar rejuvenating benefits for old mice as young mouse blood does.

"We saw these astounding effects," he says. "The human blood had beneficial effects on every organ we've studied so far."

Now, the final step – giving young human blood plasma to older people with a medical condition – is about to begin. Getting approval to perform the experiment in humans has been relatively simple, says Wyss-Coray, thanks to the long safety record of blood transfusions. He warns against swapping blood at home because transfusions need to be screened for disease, matched for blood type and the plasma needs to be separated out. "Certainly you can't drink the blood," he says. "Although obviously we haven't tried that experiment."

So in early October, a team at Stanford School of Medicine will give a transfusion of blood plasma donated by people under 30 to older volunteers with mild to moderate Alzheimer's.

Following the impressive results in animal experiments, the team hopes to see immediate improvements in cognition, but Wyss-Coray cautions that it is still very experimental. "We will assess cognitive function immediately before and for several days after the transfusion, as well as tracking each person for a few months to see if any of their family or carers report any positive effects," he says. "The effects might be transient, but even if it's just for a day it is a proof of concept that is worth pursuing."

All researchers involved in the work agree that GDF11 is unlikely to be the only factor that keeps organs youthful. "It's too optimistic to think there would be just one factor," says Francesco Loffredo, who studies the effects of young blood in old animals at Harvard University. "It's much more likely to be several factors that exert these effects in combination."

Loffredo says the approach of testing the effects of young blood in people with Alzheimer's is fascinating, but reckons in the long-term it is best to continue to strive to identify the individual factors that are exerting the rejuvenating effects so that they can be translated to humans more easily. "Imagine if you had to be transfused with young blood all the time – it's hard to imagine as a therapy. Who is going to be donating all this blood?" he asks.

Wyss-Coray agrees. "It would be great if we could identify several factors that we could boost in older people," he says. "Then we might be able to make a drug that does the same thing. We also want to know what organ in the body produces these factors. If we knew that, maybe we could stimulate that tissue in older people."

Chemotherapy aid

Alessandro Laviano at the Sapienza University of Rome in Italy says that the research on diseases of ageing certainly holds promise, but he is more interested in the potential use of young blood in chronic disease. People with cancer who resist muscle loss have better chances of survival, he says. "So I'd like to consider the possibility of using these youthful factors in young blood to reduce the muscle wasting that occurs during chemotherapy."

Before moving to clinical trials in people with cancer we need to learn more about the dynamics of the beneficial factors in blood, says Laviano, such as when they are at their peak. Do we reach a peak at 5 or 35 years? "We just don't know," he says. He would also like to investigate what happens when you give "too much" GDF11 – does it result in extra benefit or a negative outcome?

Laviano is currently looking at the effect of GDF11 on tumours in animals to see if it inhibits their growth, but he would also like to start an observational trial in humans. It would be very simple, he says, to find the age of the blood given to people receiving transfusions and test whether it has any effect.

"I certainly think that this therapy might be beneficial in a number of different conditions," says Wyss-Coray. "Blood might contain the fountain of youth after all. And it is within us all – that's the crazy thing. It just loses its power as we age."

Lance el tramposo. A buenas horas...

Ahora que el ciclista Lance Amstrong  ha reconocido que  ganó 7 Tours dopándose queda claro que  decir que una  determinada perosna "ha pasado el control antidopaje"  no significa NADA salvo que se diga las carácteristicas de la técnica empleada, la sensibilidad de la técnica, el porcentaje de falsos positivos, de verdaderos negativos, la especificidad de la  prueba y un largo etcétera.
Es el ejemplo claro de que se puede engañar y no ser detectado.
¿Cuántas veces pasó el americano impasible los controles antidopaje?
Un montón de veces.

¿Tuvo ayudas? Naturalmente. Se ha forrado el riñón delinquiendo, si delinquiendo. Y no pasa nada. ¿Tuvo  médicos corruptos a su lado ayudándole? Evidentemente y todos sabemos sus nombres.  ¿Y que? Nada, absolutamente nada, ahora todos gozan de buenas cuentas corrientes y las  posibles demandas y  denuncias se la traen al pairo al tejano. Incluso sacará más dinero ofreciendo entrevistas o  diciendo que  ahora trabajará al otro lado de la ley

.Corrupción. asco y vergüenza . Entrenadores que miraban hacía otro lado. Galenos con pocos escrúpulos, salvo los de trincar y salir arreando, que es gerundio.

Ahora  el impasible tejano  ( porque menudo rostro pétreo tiene), ahora irá de bueno , de  compungido, de  redimido  diciendo que  "quiere mejorrar las técnicas de detección", o "que  se arrepiente, que se ha equivocado " y "que no lo volverá a hacer mas".

Por poner un  ejempo  próximo, campechano.

Antioxidantes?...Que cerdada.

Del cerdo dicen que se aprovecha todo...pues si, incluso en el siguiente artículo se describe como se ha aislado un antioxidante de la hemoglobina porcina.
De otros cerdos, mejor ignorarlos.
Y hablar de antioxidantes supone entrar en el  maravilloso mundo de los " scevenger agents" o antioxidantes ó agentes  antienvejecimiento celular, que bloquearían la acción nociva de éstos R.L. 
 sobre las membranas  celulares de los  altamente reactivos radicales libres ( como el  ión oxhidrilo) responsables de isquemia, daño celular ,  alteraciones celulares,  etc...
El uso clinico de los antioxidantes   como retardantes del enbejecimiento es  un campo interesantísimo.

Más en :
International Journal of Food Science & Technology, 2012, 47, 148 - 154
Qian Sun, Yongkang Luo, Huixing Shen, Xue Li, Lei Yao
Abstract: Porcine haemoglobin, which is normally discarded as a by-product of meat industry, was hydrolysed using pepsin, AS1398 neutrase, trypsin, flavorzyme, papain and alcalase respectively. The peptic hydrolysate exhibited the highest antioxidant activities than those of other hydrolysates, which was separated using ultrafiltration membranes, and consecutively using chromatographic methods including ion-exchange chromatography on SP Sephadex C-25 column, gel filtration chromatography on Sephadex G-25 column and reversed-phase high performance liquid chromatography. Finally, a novel antioxidant peptide from porcine haemoglobin (APPH) was purified, and its sequence was identified to be ARRLGHDFNPDVQAA (1666 Da) using mass spectrometry. APPH exhibited significant higher lipid peroxidation inhibitory ability than that of alpha-tocopherol as positive control (P < 0.05), and efficiently quenched hydroxyl radical (IC₅₀ = 26.9 µm). APPH agrees with the 115-129 residues of the beta-chain from porcine haemoglobin. These results indicate that APPH would be a beneficial ingredient for functional food and pharmaceuticals.