Couldn't authenticate you error (Same was working few minutes before)



I am facing strange issue, when I execute below curl command:

curl --get '' --header 'Authorization: OAuth oauth_consumer_key="IdeTxnRh9HtANPTjTLj90oPG4", oauth_nonce="de2e6ef186c9f6eabc20c42f448bde8e", oauth_signature="WyfHUpHeN2AJTt9WLcbKOe1xF2c%3D", oauth_signature_method="HMAC-SHA1", oauth_timestamp=1398430376, oauth_token="2462659622-ZrSWcU3KjTm57Qp9ZB68jX6kOR1OULLpLGHkSgP", oauth_version="1.0"'

I was able to get the json data successfully sometime before, now if I try to execute I get the error:

{"errors":[{"message":"Could not authenticate you","code":32}]}

I don’t know suddenly why I am getting this error? (and yes I am changing timestamp as and when I execute). Is there any automated key expiration happening here? If yes, I should keep on changing the key every few minutes?